WillScot (WSC) S-4/ARegistration of securities issued in business combination transactions (amended)

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ANNEX A
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As filed with the Securities and Exchange Commission on May 1, 2020

Registration No. 333-237746

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

AMENDMENT NO. 1
TO

FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

WillScot Corporation
(Exact name of registrant as specified in its charter)

901 S. Bond Street, Suite 600
Baltimore, MD 21231
(410) 931-6000
(Address, including zip code, and telephone number, including
area code, of registrant's principal executive offices)

Hezron Timothy Lopez
Vice President, General Counsel & Corporate Secretary
901 S. Bond Street, Suite 600
Baltimore, MD 21231
(410) 931-6000
(Name, address, including zip code, and telephone number, including
area code, of agent for service)

          Approximate date of commencement of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective and all other conditions to the proposed merger described in the enclosed joint proxy statement/prospectus have been satisfied or waived.

          If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box.    o

          If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

          If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

          Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

          If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.    o

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)    o

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)    o

          The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information in this joint proxy statement/prospectus is not complete and may be changed. We may not sell the securities offered by this joint proxy statement/prospectus until the registration statement filed with the U.S. Securities and Exchange Commission is effective. This joint proxy statement/prospectus does not constitute an offer to sell or a solicitation of an offer to buy any securities in any jurisdiction where an offer, solicitation or sale is not permitted.

PRELIMINARY—SUBJECT TO COMPLETION—DATED MAY 1, 2020

To the Stockholders of WillScot Corporation and Mobile Mini, Inc.

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

Dear WillScot Stockholders and Mobile Mini Stockholders:

        On March 1, 2020, WillScot Corporation ("WillScot"), Picasso Merger Sub, Inc., a wholly owned subsidiary of WillScot ("Merger Sub"), and Mobile Mini, Inc. ("Mobile Mini") entered into an Agreement and Plan of Merger, as may be amended from time to time (the "Merger Agreement"), pursuant to which, subject to the approval of WillScot stockholders and Mobile Mini stockholders and the satisfaction or (to the extent permitted by law) waiver of other specified closing conditions, WillScot and Mobile Mini will combine in a stock-for-stock merger of equals. At the effective time of the merger (the "Effective Time"), Merger Sub will merge with and into Mobile Mini (the "Merger"), with Mobile Mini surviving the Merger and becoming a wholly owned subsidiary of WillScot. As of the Effective Time, the name of WillScot will be changed (the "Combined Company"). The Combined Company will have a single series of common stock, par value $0.0001 per share (the "Combined Company Common Stock"), outstanding shares of which will be listed for trading on the Nasdaq Capital Market. The Combined Company's name and ticker symbol will be mutually agreed upon between the parties prior to the Effective Time.

        Pursuant to the Merger Agreement, at the Effective Time, each issued and outstanding share of Mobile Mini Common Stock will be converted into the right to receive 2.4050 shares of WillScot Class A Common Stock (the "Merger Consideration"), less any applicable withholding taxes and, if applicable, cash in lieu of fractional shares. Immediately following Mobile Mini stockholders' receipt of the Merger Consideration, all issued and outstanding shares of WillScot Class A Common Stock will be reclassified as and converted into shares of Combined Company Common Stock. For more details on the Merger Consideration, see "The Merger Agreement—Merger Consideration."

        Based on the current number of shares of Mobile Mini Common Stock outstanding and reserved for issuance, and the current number of shares of WillScot Class A Common Stock outstanding and reserved for issuance, we estimate that, immediately following completion of the Merger, former holders of Mobile Mini Common Stock will own approximately 46% of the issued and outstanding shares of Combined Company Common Stock and pre-Merger holders of WillScot Class A Common Stock will own approximately 54% of the issued and outstanding shares of Combined Company Common Stock.

        The Combined Company's Board of Directors (the "Combined Company Board") will consist of 11 members, which will be comprised of: (i) six directors designated by WillScot, two of whom will be chosen by the TDR Parties (as defined below), and (ii) five directors designated by Mobile Mini. The Combined Company's management team will, pursuant to employment agreements entered into in connection with the signing of the Merger Agreement, consist of: (i) Bradley Soultz, the current Chief Executive Officer of WillScot, as the Chief Executive Officer of the Combined Company, (ii) Kelly Williams, the current President and Chief Executive Officer of Mobile Mini, as the President and Chief Operating Officer of the Combined Company, (iii) Timothy Boswell, the current Chief Financial Officer of WillScot, as the Chief Financial Officer of the Combined Company, (iv) Christopher Miner, the current General Counsel of Mobile Mini, as the Senior Vice President, General Counsel and Secretary of the Combined Company and (v) Hezron T. Lopez, the current General Counsel of WillScot, as the Chief Human Resources Officer of the Combined Company. The Combined Company's headquarters, as of the Effective Time, will be located in Phoenix, Arizona. For additional information about the governance of the Combined Company following the Merger, see "The Merger—Governance of the Combined Company."

        In connection with the parties' entry into the Merger Agreement, Mobile Mini entered into a voting agreement (the "Voting Agreement") with TDR Capital LLP and certain of its affiliates (the "TDR Parties") whereby the TDR Parties agreed, among other things and subject to the terms of the Voting Agreement, to vote all of their shares of WillScot Class A Common Stock and WillScot Class B Common Stock in favor of (i) the issuance of the Merger Consideration and (ii) the approval of the amended and restated certificate of incorporation of the Combined Company (the "A&R Charter"), to be adopted at the Effective Time.

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        At the closing of the Merger, the TDR Parties will enter into a shareholders agreement with the Combined Company which will provide for, among other things, (a) certain TDR Parties' right to nominate (i) two directors to the Combined Company Board for so long as the TDR Parties beneficially own at least 15% of the issued and outstanding shares of Combined Company Common Stock and (ii) one director to the Combined Company Board for so long as the TDR Parties beneficially own at least 5%, but less than 15%, of the issued and outstanding shares of Combined Company Common Stock, (b) certain standstill obligations of the TDR Parties with respect to the Combined Company Common Stock, and (c) certain restrictions on the TDR Parties' ability to transfer shares of Combined Company Common Stock, including a lock-up period of six months after the closing of the Merger and restrictions on the volume of shares of Combined Company Common Stock that can be transferred by the TDR Parties following the expiration of the lock-up. As of the Effective Time, the TDR Parties are expected to own 26% of the issued and outstanding shares of Combined Company Common Stock. For more details on the Voting Agreement and the Shareholders Agreement, see "The Merger—The Voting Agreement and Shareholders Agreement."

        Each of WillScot and Mobile Mini will hold a virtual special meeting of its respective stockholders to vote on the proposals necessary to complete the Merger and the related transactions contemplated by the Merger Agreement. Each of WillScot and Mobile Mini has chosen to hold its special meeting solely via the Internet and not in a physical location given the current public health impact of coronavirus (COVID-19) and the desire to promote the health and safety of its stockholders, as well as its directors, officers, employees and other constituents. Information about each meeting, the Merger and the other business to be considered by stockholders at each special meeting is contained in this joint proxy statement/prospectus. Any stockholder entitled to attend and vote at the applicable special meeting is entitled to appoint a proxy to attend and vote on such stockholder's behalf. Such proxy need not be a holder of WillScot Common Stock or Mobile Mini Common Stock. We urge you to read this joint proxy statement/prospectus and the annexes and documents incorporated by reference herein carefully.You should also carefully consider the risks that are described in the "Risk Factors" section beginning on page 30.

        Your vote is very important regardless of the number of shares of WillScot Common Stock or Mobile Mini Common Stock that you own. The Merger cannot be completed without: (1) the adoption of the Merger Agreement by the affirmative vote of the holders of a majority of the issued and outstanding shares of Mobile Mini Common Stock entitled to vote (in person or by proxy) at the Mobile Mini special meeting; (2) the approval of the issuance of shares of WillScot Class A Common Stock to the stockholders of Mobile Mini as the Merger Consideration by the affirmative vote of the holders of a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock entitled to vote on the matter at a duly called and held meeting of WillScot stockholders at which a quorum is present (in person or by proxy), voting together as a single class; and (3) the approval of the A&R Charter by the affirmative vote of each of: (i) the holders of a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock that are entitled to vote, voting together as a single class, (ii) the holders of a majority of the issued and outstanding shares of WillScot Class A Common Stock, voting as a separate class, and (iii) the holders of a majority of the issued and outstanding shares of WillScot Class B Common Stock, voting as a separate class. Completion of the Merger is not conditioned upon the approval of the Combined Company 2020 Incentive Plan (as defined below).

        Whether or not you plan to attend the live webcasts of the WillScot special meeting or the Mobile Mini special meeting, as applicable, please submit your proxy as soon as possible to make sure that your shares are represented at the applicable meeting.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the Merger or the other transactions described in this joint proxy statement/prospectus or the securities to be issued in connection with the Merger or determined if this joint proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

        The accompanying joint proxy statement/prospectus is dated [            ], 2020 and is first being mailed to stockholders of WillScot and Mobile Mini on or about [            ], 2020.

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WILLSCOT CORPORATION
901 S. Bond Street, Suite 600
Baltimore, Maryland 21231

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
To be held on [            ], 2020

To the Stockholders of WillScot Corporation:

        We are pleased to invite you to attend, and notice is hereby given that WillScot Corporation ("WillScot"), will hold, a special meeting of its stockholders (the "WillScot special meeting"), via live webcast through the link [                ] (the "WillScot special meeting website") on [            ], 2020 at [            ]  a.m. Eastern Time.

        WillScot has chosen to hold the WillScot special meeting solely via live webcast and not in a physical location given the current public health impact of coronavirus (COVID-19) and our desire to promote the health and safety of WillScot stockholders, as well as WillScot directors, officers, employees and other constituents. You will need the 16-digit control number included on your proxy card if you are a stockholder of record or included with your voting instruction form provided by your bank, broker or other nominee if you hold your shares of WillScot Common Stock in street name through an account with an intermediary to attend the WillScot special meeting. The WillScot special meeting will be held for the following purposes:

1.

Approval of the WillScot Stock Issuance. To vote on a proposal to approve the issuance of shares of WillScot's Class A common stock, par value $0.0001 per share (the "WillScot Class A Common Stock"), to stockholders of Mobile Mini Inc. ("Mobile Mini") in connection with the merger of equals (the "Merger") contemplated by the Agreement and Plan of Merger (as may be amended from time to time, the "Merger Agreement"), dated as of March 1, 2020, by and among WillScot, Mobile Mini and Picasso Merger Sub, Inc., a wholly owned subsidiary of WillScot (the "WillScot Stock Issuance Proposal");



2.

Approval of the Combined Company Charter Amendment. To vote on a proposal to approve and adopt the amended and restated certificate of incorporation of WillScot, to be renamed as mutually agreed upon between the parties prior to the Effective Time (the "Combined Company"), at the closing of the Merger (the "A&R Charter"), in the form attached as Annex B to this joint proxy statement/prospectus (the "Combined Company Charter Amendment Proposal");



3.

Approval of the 2020 Incentive Plan. To vote on a proposal to amend and restate, in its entirety, the WillScot Corporation 2017 Incentive Award Plan, as amended (the "WillScot 2017 Incentive Plan"), as the Combined Company 2020 Incentive Award Plan (the "Combined Company 2020 Incentive Plan"), to: (i) increase the number of shares of Combined Company Common Stock authorized for issuance under the Combined Company 2020 Incentive Plan by 5,000,000 shares, (ii) revise the definition of "Change in Control" to align with such definition as set forth in the employment agreements for Messrs. Soultz, Williams, Boswell, Miner and Lopez, entered into in connection with the signing of the Merger Agreement and discussed in detail elsewhere in this joint proxy statement/prospectus, and make certain other conforming changes and updates to reflect changes in law and practice, and (iii) rename the WillScot 2017 Incentive Plan as the "Combined Company 2020 Incentive Award Plan," and change all references to WillScot therein to the Combined Company, in each case, as set forth in the form of Combined Company 2020 Incentive Plan attached as Annex E to this joint proxy statement/prospectus, and to be effective upon, and subject to, the closing of the Merger and

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the other transactions contemplated by the Merger Agreement (the "2020 Incentive Plan Proposal"); and

4.

Adjournment of the WillScot Special Meeting. To vote on a proposal to approve the adjournment of the WillScot special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies in the event there are not sufficient votes at the time of the WillScot special meeting to approve the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal (the "WillScot Adjournment Proposal," and together with the WillScot Stock Issuance Proposal, the Combined Company Charter Amendment Proposal and the 2020 Incentive Plan Proposal, the "WillScot Proposals").

        WillScot will transact no other business at the WillScot special meeting, except such business as may properly be brought before the WillScot special meeting or any adjournment or postponement thereof. Please refer to the joint proxy statement/prospectus of which this notice is a part for further information with respect to the business to be transacted at the WillScot special meeting.

        The WillScot board of directors (the "WillScot Board") has fixed the close of business on [            ], 2020 as the record date for the WillScot special meeting (the "WillScot Record Date"). Only stockholders of record at that time are entitled to receive notice of, and to vote at, the WillScot special meeting or any adjournment or postponement thereof. WillScot is commencing its solicitation of proxies on or about [            ], 2020. WillScot will continue to solicit proxies until the date of the WillScot special meeting. A list of stockholders of record will be available during the WillScot special meeting for inspection by stockholders at [            ].

        Completion of the Merger is conditioned upon, among other things, (i) approval of the WillScot Stock Issuance Proposal by the WillScot stockholders, which requires the affirmative vote of the holders of a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B common stock, par value $0.0001 per share (the "WillScot Class B Common Stock" and together with the WillScot Class A Common Stock, the "WillScot Common Stock"), entitled to vote at a duly called and held meeting of WillScot stockholders at which a quorum is present (in person or by proxy), voting together as a single class, and (ii) approval of the Combined Company Charter Amendment Proposal, which requires the affirmative vote of holders of each of (a) a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock that are entitled to vote, voting together as a single class, (b) a majority of the issued and outstanding shares of WillScot Class A Common Stock, voting as a separate class, and (c) a majority of the issued and outstanding shares of WillScot Class B Common Stock, voting as a separate class.

        The WillScot Board unanimously approved and declared advisable the Merger Agreement and the transactions contemplated by the Merger Agreement and determined that the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, certain governance arrangements, the WillScot Stock Issuance, the Combined Company Charter Amendment and the 2020 Incentive Plan are advisable and fair to and in the best interests of WillScot and its stockholders, and unanimously recommends that WillScot stockholders vote:

•

"FOR" the WillScot Stock Issuance Proposal;



•

"FOR" the Combined Company Charter Amendment Proposal;



•

"FOR" the 2020 Incentive Plan Proposal; and



•

"FOR" the WillScot Adjournment Proposal.

        Your vote is very important regardless of the number of shares of WillScot Common Stock that you own. A failure to vote your shares, or to provide instructions to your bank, brokers or nominee as to how to vote your shares, is the equivalent of a vote against the Combined Company Charter Amendment Proposal. Whether or not you expect to attend the WillScot special meeting in person via live webcast, to ensure your representation at the WillScot special meeting, we urge you to submit a proxy to vote your shares as promptly as possible by (1) visiting the Internet site listed on the WillScot proxy card, (2) calling the toll-free number listed on the WillScot proxy card or (3) submitting your WillScot proxy card by mail by using the provided self-addressed, stamped envelope. Submitting a proxy will not prevent you from voting in person via live webcast, but it will help to secure a quorum

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and avoid added solicitation costs. Any eligible holder of WillScot Common Stock who is present at the WillScot special meeting may vote in person via live webcast, thereby revoking any previous proxy. In addition, a proxy may also be revoked in writing before the WillScot special meeting in the manner described in the accompanying joint proxy statement/prospectus. If your shares are held in the name of a bank, broker or other nominee, please follow the instructions on the voting instruction card furnished by the bank, broker or other nominee.

        You may log into the WillScot special meeting website and enter your control number beginning fifteen (15) minutes before the commencement of the WillScot special meeting. The meeting platform is fully supported across browsers (Internet Explorer, Firefox, Chrome, and Safari) and devices (desktops, laptops, tablets, and cell phones) running the most updated version of applicable software and plugins. Participants should ensure that they have a strong WiFi connection wherever they intend to participate in the WillScot special meeting. Participants should also give themselves plenty of time to log in and ensure that they can hear streaming audio prior to the start of the meeting.

        Instructions on how to attend and participate online at the WillScot special meeting, including how to demonstrate proof of stock ownership, ask questions and vote, are posted at [            ].

        The enclosed joint proxy statement/prospectus provides a detailed description of the Merger and the Merger Agreement and the other matters to be considered at the WillScot special meeting. We urge you to carefully read this joint proxy statement/prospectus, including any documents incorporated by reference herein, and the annexes in their entirety. If you have any questions concerning any of the proposals in this notice, the Merger or the joint proxy statement/prospectus, would like additional copies or need help voting your shares of WillScot Common Stock, please contact WillScot's proxy solicitor:

Georgeson LLC
1290 Avenue of the Americas, 9th Floor
New York, NY 10104
Telephone: 866-785-7395 (toll-free)
781-575-2137 (for all those outside of the U.S.)

Baltimore, Maryland
[            ], 2020

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MOBILE MINI, INC.
4646 E. Van Buren Street, Suite 400
Phoenix, Arizona 85008

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

To the Stockholders of Mobile Mini, Inc.:

        We are pleased to invite you to attend, and notice is hereby given that Mobile Mini, Inc. ("Mobile Mini") will hold, a special meeting of its stockholders (the "Mobile Mini special meeting"), via live webcast through the link [                ] (the "Mobile Mini special meeting website"), on [                    ], [        ], 2020 at [            ] Phoenix local time.

        Mobile Mini has chosen to hold the Mobile Mini special meeting solely via live webcast and not in a physical location given the current public health impact of coronavirus (COVID-19) and our desire to promote the health and safety of Mobile Mini stockholders, as well as Mobile Mini directors, officers, employees and other constituents. You will need the 16-digit control number included on your proxy card if you are a stockholder of record or included with your voting instruction form provided by your bank, broker or other nominee if you hold your shares of Mobile Mini Common Stock in street name through an account with an intermediary to attend the Mobile Mini special meeting. The Mobile Mini special meeting will be held for the following purposes:

1.

Adoption of the Merger Agreement. To vote on a proposal to approve and adopt the Agreement and Plan of Merger, dated as of March 1, 2020 (as may be amended from time to time, the "Merger Agreement"), by and among WillScot Corporation ("WillScot"), Mobile Mini and Picasso Merger Sub, Inc., a wholly owned subsidiary of WillScot, which is further described in the section entitled "The Merger Agreement," a copy of which Merger Agreement is attached as Annex A to the joint proxy statement/prospectus accompanying this notice (the "Mobile Mini Merger Proposal");



2.

Mobile Mini Merger-Related Compensation. To vote on a proposal to approve, by advisory (non-binding) vote, certain compensation arrangements that may be paid or become payable to Mobile Mini's named executive officers in connection with the merger of equals (the "Merger") contemplated by the Merger Agreement (the "Mobile Mini Merger-Related Compensation Proposal"); and



3.

Adjournment of the Mobile Mini Special Meeting. To vote on a proposal to approve the adjournment of the Mobile Mini special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies in the event there are not sufficient votes at the time of the Mobile Mini special meeting to approve the Mobile Mini Merger Proposal (the "Mobile Mini Adjournment Proposal," and together with the Mobile Mini Merger Proposal and the Mobile Mini Merger-Related Compensation Proposal, the "Mobile Mini Proposals").

        Mobile Mini will transact no other business at the Mobile Mini special meeting, except such business as may properly be brought before the Mobile Mini special meeting or any adjournment or postponement thereof. Please refer to the joint proxy statement/prospectus of which this notice is a part for further information with respect to the business to be transacted at the Mobile Mini special meeting.

        The Mobile Mini board of directors (the "Mobile Mini Board") has fixed the close of business on [                    ], 2020 as the record date for the Mobile Mini special meeting (the "Mobile Mini Record Date"). Only Mobile Mini stockholders of record at that time are entitled to receive notice of, and to

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vote at, the Mobile Mini special meeting or any adjournment or postponement thereof. Mobile Mini is commencing its solicitation of proxies on or about [                    ], 2020. Mobile Mini will continue to solicit proxies until the date of the Mobile Mini special meeting. A list of stockholders of record will be available during the Mobile Mini special meeting for inspection by stockholders at [                ].

        Completion of the Merger is conditioned upon, among other things, adoption of the Merger Agreement by the Mobile Mini stockholders, which requires the affirmative vote of the holders of a majority of the issued and outstanding shares of Mobile Mini Common Stock entitled to vote (in person or by proxy) at the Mobile Mini special meeting. Stockholders who attend the Mobile Mini special meeting will be considered to be attending the meeting in person.

        The Mobile Mini Board has approved and declared advisable the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger; has determined that the Merger Agreement and transactions contemplated by the Merger Agreement, including the Merger, are fair to and in the best interests of Mobile Mini stockholders; and recommends that Mobile Mini stockholders vote:

•

"FOR" the Mobile Mini Merger Proposal;



•

"FOR" the Mobile Mini Merger-Related Compensation Proposal; and



•

"FOR" the Mobile Mini Adjournment Proposal.

        Your vote is very important, regardless of the number of shares of Mobile Mini Common Stock that you own. A failure to vote your shares, or to provide instructions to your bank, broker or nominee as to how to vote your shares, is the equivalent of a vote against the Mobile Mini Merger Proposal. Whether or not you expect to attend the Mobile Mini special meeting in person via live webcast, to ensure your representation at the Mobile Mini special meeting, we urge you to submit a proxy to vote your shares as promptly as possible by (1) visiting the Internet site listed on the Mobile Mini proxy card, (2) calling the toll-free number listed on the Mobile Mini proxy card or (3) submitting your Mobile Mini proxy card by mail by using the provided self-addressed, stamped envelope. Submitting a proxy will not prevent you from voting in person via live webcast, but it will help to secure a quorum and avoid added solicitation costs. Any eligible holder of Mobile Mini Common Stock who is present at the Mobile Mini special meeting may vote in person via live webcast, thereby revoking any previous proxy. In addition, a proxy may also be revoked in writing before the Mobile Mini special meeting in the manner described in the accompanying joint proxy statement/prospectus. If your shares are held in the name of a bank, broker or other nominee, please follow the instructions on the voting instruction card furnished by the bank, broker or other nominee.

        You may log into the Mobile Mini special meeting website and enter your control number beginning fifteen (15) minutes before the commencement of the Mobile Mini special meeting. The meeting platform is fully supported across browsers (Internet Explorer, Firefox, Chrome, and Safari) and devices (desktops, laptops, tablets, and cell phones) running the most updated version of applicable software and plugins. Participants should ensure that they have a strong WiFi connection wherever they intend to participate in the Mobile Mini special meeting. Participants should also give themselves plenty of time to log in and ensure that they can hear streaming audio prior to the start of the meeting.

        Instructions on how to attend and participate online at the Mobile Mini special meeting, including how to demonstrate proof of stock ownership, ask questions and vote, are posted at [            ].

        The enclosed joint proxy statement/prospectus provides a detailed description of the Merger and the Merger Agreement and the other matters to be considered at the Mobile Mini special meeting. We urge you to carefully read this joint proxy statement/prospectus, including any documents incorporated by reference herein, and the annexes in their entirety. If you have any questions concerning any of the proposals in this notice, the Merger or the joint proxy statement/prospectus, would like additional

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copies or need help voting your shares of Mobile Mini Common Stock, please contact Mobile Mini's proxy solicitor or Mobile Mini:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, NY 10022
Stockholders May Call Toll-Free: (877) 800-5195
Banks & Brokers May Call Collect: (212) 750-5833

OR

Mobile Mini, Inc.
4646 E. Van Buren Street, Suite 400
Phoenix, Arizona 85008
Attention: Investor Relations
Telephone: (480) 894-6311
E-mail: etadano@mobilemini.com

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ADDITIONAL INFORMATION

        The accompanying joint proxy statement/prospectus incorporates by reference important business and financial information about WillScot and Mobile Mini from other documents that are not included in or delivered with the accompanying joint proxy statement/prospectus. For a listing of the documents incorporated by reference into the accompanying joint proxy statement/prospectus, see the section entitled "Where You Can Find More Information."

        You can obtain any of the documents incorporated by reference into the accompanying joint proxy statement/prospectus by requesting them in writing or by telephone as follows:

        To receive timely delivery of the documents in advance of the WillScot special meeting and the Mobile Mini special meeting, you should make your request no later than [            ], 2020.

        You may also obtain any of the documents incorporated by reference into the accompanying joint proxy statement/prospectus without charge through the Securities and Exchange Commission website atwww.sec.gov. In addition, you may obtain copies of documents filed by WillScot with the SEC on WillScot's website athttp://www.willscot.com under the tab "Investors," then under the heading "Financial Information" or by contacting WillScot's Corporate Secretary at WillScot Corporation, 901 S. Bond Street, Suite 600, Baltimore, Maryland 21231. You may also obtain copies of documents filed by Mobile Mini with the SEC on Mobile Mini's Internet website athttp://www.mobilemini.com under the tab "Company—Investor Relations" and then under the heading "Filings & Financials—SEC Filings" or by contacting Mobile Mini's Investor Relations at Mobile Mini, Investor Relations, 4646 E. Van Buren Street, Suite 400, Phoenix, Arizona 85008.

        We are not incorporating the contents of the websites of the SEC, WillScot, Mobile Mini or any other entity or any other website into the accompanying joint proxy statement/prospectus. We are providing the information about how you can obtain certain documents that are incorporated by reference into the accompanying joint proxy statement/prospectus at these websites only for your convenience.

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ABOUT THIS JOINT PROXY STATEMENT/PROSPECTUS

        This joint proxy statement/prospectus, which forms part of a registration statement on Form S-4 filed with the SEC by WillScot (File No. 333-237746), constitutes a prospectus of WillScot under Section 5 of the Securities Act with respect to the shares of WillScot Class A Common Stock to be issued to Mobile Mini stockholders as Merger Consideration pursuant to the Merger Agreement. This document also constitutes a joint proxy statement of each of WillScot and of Mobile Mini under Section 14(a) of the Exchange Act. It also constitutes a notice of meeting with respect to the Mobile Mini special meeting, at which Mobile Mini stockholders will be asked to consider and vote upon the Mobile Mini Proposals and certain other related matters, and it constitutes a notice of meeting with respect to the WillScot special meeting, at which WillScot stockholders will be asked to consider and vote upon the WillScot Proposals and certain other related matters.

        WillScot has supplied all information contained or incorporated by reference into this joint proxy statement/prospectus relating to WillScot and Merger Sub, and Mobile Mini has supplied all such information relating to Mobile Mini.

        You should rely only on the information contained in or incorporated by reference into this joint proxy statement/prospectus. WillScot and Mobile Mini have not authorized anyone to provide you with information that is different from that contained in or incorporated by reference into this joint proxy statement/prospectus. This joint proxy statement/prospectus is dated as of the date set forth above on the cover page of this joint proxy statement/prospectus, and you should not assume that the information contained in this joint proxy statement/prospectus is accurate as of any date other than such date. Further, you should not assume that the information incorporated by reference into this joint proxy statement/prospectus is accurate as of any date other than the date of the incorporated document. Neither the mailing of this joint proxy statement/prospectus to WillScot stockholders or Mobile Mini stockholders nor the issuance by WillScot of shares of WillScot Class A Common Stock as Merger Consideration pursuant to the Merger Agreement will create any implication to the contrary.

        This joint proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

        Unless otherwise indicated or as the context otherwise requires, all references in this joint proxy statement/prospectus to:

•

"2020 Incentive Plan Proposal" refers to the proposal to amend and restate, in its entirety, the WillScot Corporation 2017 Incentive Plan, as amended, as the Combined Company 2020 Incentive Award Plan, as set forth in the form of Combined Company 2020 Incentive Plan attached as Annex E to this joint proxy statement/prospectus, and to be effective upon, and subject to, the closing of the Merger and the other transactions contemplated by the Merger Agreement



•

"2023 Annual Stockholders Meeting" refers to the 2023 annual meeting of stockholders of the Combined Company



•

"A&R Bylaws" refers to the bylaws of the Combined Company, as amended and restated at the Effective Time



•

"A&R Charter" refers to the certificate of incorporation of WillScot, as amended and restated at the Effective Time, which will be the certificate of incorporation of the Combined Company



•

"Barclays" refers to Barclays Capital Inc.



•

"Code" refers to the Internal Revenue Code of 1986, as amended



•

"Combined Company" refers to WillScot following the Effective Time (at which time WillScot will be renamed, as mutually agreed upon between the parties)



•

"Combined Company Board" refers to the board of directors of the Combined Company

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•

"Combined Company Charter Amendment Proposal" refers to the proposal that the WillScot stockholders approve and adopt the A&R Charter



•

"Combined Company Common Stock" refers to the common stock, par value $0.0001 per share, of the Combined Company, following the effectiveness of the A&R Charter



•

"DGCL" refers to the General Corporation Law of the State of Delaware



•

"Effective Time" refers to the effective time of the Merger



•

"Exchange Act" refers to the Securities Exchange Act of 1934, as amended



•

"Exchange Ratio" refers to 2.4050 shares of WillScot Class A Common Stock per share of Mobile Mini Common Stock



•

"Excluded Shares" refers to shares of Mobile Mini Common Stock held immediately prior to the Effective Time by Mobile Mini as treasury stock or owned by a subsidiary of Mobile Mini



•

"GAAP" refers to United States generally accepted accounting principles



•

"Goldman Sachs" refers to Goldman Sachs & Co. LLC



•

"HSR Act" refers to the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended



•

"IRS" refers to the Internal Revenue Service



•

"Merger" refers to the merger of Merger Sub with and into Mobile Mini, with Mobile Mini being the surviving corporation



•

"Merger Agreement" refers to the Agreement and Plan of Merger, dated as of March 1, 2020, by and among WillScot, Merger Sub and Mobile Mini, as may be amended from time to time



•

"Merger Consideration" refers to the shares of WillScot Class A Common Stock to be issued to the Mobile Mini stockholders in exchange for their shares of Mobile Mini Common Stock



•

"Merger Sub" refers to Picasso Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of WillScot



•

"Mobile Mini" refers to Mobile Mini, Inc., a Delaware corporation



•

"Mobile Mini Adjournment Proposal" refers to the proposal that the Mobile Mini stockholders adjourn the Mobile Mini special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies in the event there are not sufficient votes at the time of the Mobile Mini special meeting to approve the Mobile Mini Merger Proposal



•

"Mobile Mini Board" refers to the Board of Directors of Mobile Mini



•

"Mobile Mini Common Stock" refers to common stock, par value $0.01 per share, of Mobile Mini



•

"Mobile Mini Merger Proposal" refers to the proposal that the Mobile Mini stockholders approve and adopt the Merger Agreement



•

"Mobile Mini Merger-Related Compensation Proposal" refers to the proposal that Mobile Mini stockholders approve, by advisory (non-binding) vote, certain compensation arrangements that may be paid or become payable to Mobile Mini's named executive officers in connection with the Merger contemplated by the Merger Agreement



•

"Mobile Mini Proposals" refers to the Mobile Mini Merger Proposal, the Mobile Mini Merger-Related Compensation Proposal and the Mobile Mini Adjournment Proposal



•

"Mobile Mini Record Date" refers to [            ], 2020



•

"Mobile Mini Restricted Stock Award" refers to an unvested award of restricted shares of Mobile Mini Common Stock

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•

"Mobile Mini stockholder" or "Mobile Mini stockholders" refers to one or more holders of Mobile Mini Common Stock, as applicable



•

"Mobile Mini Stockholder Approval" refers to the affirmative vote of the holders of a majority of the issued and outstanding shares of Mobile Mini Common Stock entitled to vote (in person or by proxy) at the Mobile Mini special meeting in favor of the Mobile Mini Merger Proposal



•

"Mobile Mini special meeting" refers to the special meeting of Mobile Mini stockholders to consider and vote upon the Mobile Mini Proposals and related matters



•

"Mobile Mini special meeting website" refers to [        ]



•

"Morgan Stanley" refers to Morgan Stanley & Co. LLC



•

"Nasdaq" refers to, with respect to WillScot, WillScot Class A Common Stock, the Combined Company and Combined Company Common Stock, the Nasdaq Capital Market and, with respect to Mobile Mini and Mobile Mini Common Stock, the Nasdaq Global Select Market



•

"Sapphire Holding" refers to Sapphire Holding S.à r.l., an affiliate of TDR Capital



•

"SEC" refers to the U.S. Securities and Exchange Commission



•

"Securities Act" refers to the Securities Act of 1933, as amended



•

"Shareholders Agreement" refers to the agreement to be entered into at the Effective Time between the Combined Company and the TDR Parties, substantially in the form attached to the Merger Agreement as Exhibit F



•

"Stifel" refers to Stifel, Nicolaus & Company, Incorporated



•

"TDR Capital" refers to TDR Capital LLP



•

"TDR Holdings" refers to TDR Capital II Holdings L.P.



•

"TDR Parties" refers to one or more of Sapphire Holding, TDR Capital and TDR Holdings, as applicable



•

"Voting Agreement" refers to the Voting Agreement, dated as of March 1, 2020, by and among Mobile Mini, TDR Capital, TDR Holdings and Sapphire Holding



•

"WillScot" refers to WillScot Corporation, a Delaware corporation



•

"WillScot Adjournment Proposal" refers to the proposal that the WillScot stockholders adjourn the WillScot special meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies in the event there are not sufficient votes at the time of the WillScot special meeting to approve the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal



•

"WillScot Board" refers to the Board of Directors of WillScot



•

"WillScot Class A Common Stock" refers to the class A common stock, par value $0.0001 per share, of WillScot



•

"WillScot Class B Common Stock" refers to the class B common stock, par value $0.0001 per share, of WillScot



•

"WillScot Common Stock" refers to the WillScot Class A Common Stock and the WillScot Class B Common Stock, together



•

"WillScot Proposals" refers to the WillScot Stock Issuance Proposal, the Combined Company Charter Amendment Proposal, the 2020 Incentive Plan Proposal and the WillScot Adjournment Proposal



•

"WillScot Record Date" refers to [            ], 2020

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•

"WillScot Special Committee" refers to the special committee of the WillScot Board consisting of independent and disinterested directors established by the WillScot Board for the purpose of reviewing, evaluating and deliberating with respect to potential strategic acquisitions or other strategic transactions, including the Merger and the other transactions contemplated by the Merger Agreement



•

"WillScot special meeting" refers to the special meeting of WillScot stockholders to consider and vote upon the WillScot Proposals and related matters



•

"WillScot special meeting website" refers to [        ]



•

"WillScot Stock Issuance Proposal" refers to the proposal that WillScot stockholders approve the issuance of the shares of WillScot Class A Common Stock as Merger Consideration to the Mobile Mini stockholders in connection with the Merger



•

"WillScot stockholder" or "WillScot stockholders" refers to one or more holders of WillScot Common Stock, as applicable



•

"WillScot Stockholder Approval" refers to the affirmative vote of (i) the holders of a majority of the issued and outstanding shares of WillScot Common Stock entitled to vote at a duly called and held meeting of WillScot stockholders at which a quorum is present (in person or by proxy) approving the WillScot Stock Issuance Proposal and (ii) the holders of (a) a majority of the issued and outstanding shares of WillScot Common Stock that are entitled to vote, (b) a majority of the issued and outstanding shares of WillScot Class A Common Stock, voting as a separate class, and (c) a majority of the issued and outstanding shares of WillScot Class B Common Stock, voting as a separate class, approving the Combined Company Charter Amendment



•

"WSHC" refers to Williams Scotsman Holdings Corp.



•

"WSHC Stock" refers to shares of WSHC common stock, par value $0.0001 per share

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i

ANNEXES

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETINGS

        The following questions and answers briefly address some commonly asked questions about the Merger, the Merger Agreement, the transactions contemplated by the Merger Agreement, the WillScot special meeting and the Mobile Mini special meeting. They may not include all the information that is important to WillScot stockholders or Mobile Mini stockholders. WillScot stockholders and Mobile Mini stockholders should carefully read this entire joint proxy statement/prospectus, including the annexes and the other documents referred to or incorporated by reference herein. See the section entitled "Where You Can Find More Information" beginning on page 260 of this joint proxy statement/prospectus.

Q:    What is the Merger?

A:

WillScot, Merger Sub and Mobile Mini have entered into the Merger Agreement, a copy of which is attached as Annex A to this joint proxy statement/prospectus. The Merger Agreement contains the terms and conditions of the proposed Merger, whereby WillScot and Mobile Mini will combine in a stock-for-stock merger of equals. Under the Merger Agreement, subject to satisfaction or (to the extent permitted by law) waiver of the conditions set forth in the Merger Agreement and described hereafter, at the Effective Time, Merger Sub will merge with and into Mobile Mini, with Mobile Mini continuing as the surviving corporation and a wholly owned subsidiary of WillScot. As a result of the Merger, Mobile Mini will no longer be a publicly held company. Following the Merger, Mobile Mini Common Stock will be delisted from Nasdaq and deregistered under the Exchange Act. As of the Effective Time, the name of WillScot will be changed. Each of the WillScot Class A Common Stock and the Mobile Mini Common Stock are traded on Nasdaq under the symbols "WSC" and "MINI," respectively. The Combined Company will have a single series of common stock which will be listed for trading on Nasdaq. The Combined Company's name and ticker symbol will be mutually agreed upon between the parties prior to the Effective Time.

Q:    Why am I receiving these materials?

A:

You are receiving this joint proxy statement/prospectus to help you decide how to vote your shares of WillScot Common Stock or Mobile Mini Common Stock with respect to the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal or the Mobile Mini Merger Proposal, as applicable, and any other matters to be considered at the applicable company's special meeting.

The Merger cannot be completed unless, among other things, (1) WillScot stockholders approve the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal at the WillScot special meeting and (2) Mobile Mini stockholders approve the Mobile Mini Merger Proposal at the Mobile Mini special meeting.

This joint proxy statement/prospectus constitutes both a joint proxy statement of WillScot and Mobile Mini and a prospectus of WillScot. It is a joint proxy statement because each of the WillScot Board and the Mobile Mini Board is soliciting proxies from its respective stockholders. It is a prospectus because WillScot will issue shares of WillScot Class A Common Stock in exchange for outstanding shares of Mobile Mini Common Stock (other than Excluded Shares) in the Merger. Immediately following Mobile Mini stockholders' receipt of WillScot Class A Common Stock in the Merger, all issued and outstanding shares of WillScot Class A Common Stock will be reclassified as and converted into shares of Combined Company Common Stock upon the filing of the A&R Charter. Information about the WillScot special meeting, the Mobile Mini special meeting, the Merger, the Merger Agreement and the other business to be considered by WillScot stockholders at the WillScot special meeting and Mobile Mini stockholders at the Mobile Mini special meeting is contained in this joint proxy statement/prospectus. WillScot stockholders and Mobile Mini stockholders should read this information carefully and in its entirety. The enclosed voting materials allow WillScot stockholders and Mobile Mini stockholders to vote their shares by proxy without attending the applicable special meeting in person via live webcast.

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Q:    What will the Combined Company be named?

A:

WillScot's certificate of incorporation will be amended and restated, effective upon the filing of the A&R Charter, to, among other things, change WillScot's name. Following completion of the Merger, the Combined Company Common Stock will be listed for trading on Nasdaq. The Combined Company's name and ticker symbol will be mutually agreed upon between the parties prior to the Effective Time.

Q:    What will Mobile Mini stockholders receive in the Merger?

A:

If the Merger is completed, each outstanding share of Mobile Mini Common Stock (other than Excluded Shares) will be converted into the Merger Consideration, which is the right to receive 2.4050 fully paid and nonassessable shares of WillScot Class A Common Stock per share of Mobile Mini Common Stock, and, if applicable, cash in lieu of fractional shares. Immediately following the Mobile Mini stockholders' receipt of the Merger Consideration, in connection with the filing of the A&R Charter, and as contemplated by the Merger Agreement, all issued and outstanding shares of WillScot's Class A Common Stock will be reclassified as and converted into shares of Combined Company Common Stock pursuant to the A&R Charter. The Merger Consideration is described in more detail in "The Merger Agreement—Merger Consideration."

Q:    What will WillScot stockholders receive in the Merger?

A:

WillScot stockholders will not receive any Merger Consideration, and their shares of WillScot Class A Common Stock will remain outstanding and, immediately following the Merger and in connection with filing of the A&R Charter, such shares will be reclassified as and converted into shares of Combined Company Common Stock. As contemplated by the Merger Agreement and the Voting Agreement, immediately prior to the Effective Time, all issued and outstanding shares of WillScot Class B Common Stock will be canceled in connection with Sapphire Holding's exchange of its shares of WSHC Stock for shares of WillScot Class A Common Stock as required by the Merger Agreement and the Voting Agreement. The Combined Company Common Stock will be listed for trading on Nasdaq. The Combined Company's ticker symbol will be mutually agreed upon between the parties prior to the Effective Time.

Q:

What respective equity stakes will WillScot stockholders and Mobile Mini stockholders hold in the Combined Company immediately following the Merger?

A:

As of the date of this joint proxy statement/prospectus, based on the current number of shares of WillScot Common Stock and Mobile Mini Common Stock outstanding and reserved for issuance, we estimate that, immediately following completion of the Merger, former holders of WillScot Common Stock will own approximately 54% of the outstanding shares of Combined Company Common Stock and former holders of Mobile Mini Common Stock will own approximately 46% of the outstanding shares of Combined Company Common Stock. The exact equity stake of WillScot stockholders and Mobile Mini stockholders in the Combined Company immediately following the Merger will depend on the number of shares of WillScot Common Stock and Mobile Mini Common Stock issued and outstanding immediately prior to the Effective Time.

Q:

Will the market value of the Merger Consideration change between the date of this joint proxy statement/prospectus and the time the Merger is completed?

A:

Yes. Although the number of shares of WillScot Class A Common Stock that holders of Mobile Mini Common Stock will receive as Merger Consideration is fixed, the market value of the Merger Consideration will fluctuate between the date of this joint proxy statement/prospectus and the completion of the Merger based upon the trading price of shares of WillScot Class A Common Stock. Any fluctuation in the trading price of shares of WillScot Class A Common Stock after the

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date of this joint proxy statement/prospectus will change the market value of the shares of WillScot Class A Common Stock that holders of Mobile Mini Common Stock will receive.

Q:

Did any WillScot stockholders enter into any agreements to vote for the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal?

A:

Yes. On March 1, 2020, in connection with WillScot's, Merger Sub's and Mobile Mini's entry into the Merger Agreement, the TDR Parties entered into a Voting Agreement with Mobile Mini pursuant to which, among other things, Sapphire Holding agreed to vote in favor of the WillScot Stock Issuance Proposal, the Combined Company Charter Amendment Proposal and the WillScot Adjournment Proposal. Sapphire Holding owned approximately 48.24% of the issued and outstanding shares of WillScot Common Stock as of the date of the Voting Agreement.

Q:

Will the TDR Parties have any right to nominate members of the Combined Company Board following the closing of the Merger?

A:

Yes. At the Effective Time, the Combined Company and the TDR Parties will enter into the Shareholders Agreement, a form of which is attached to this joint proxy statement/prospectus as Annex D. The Shareholders Agreement provides, among other things, Sapphire Holding the right to nominate: (i) two directors to the Combined Company Board for so long as the TDR Parties beneficially own at least 15% of the issued and outstanding shares of Combined Company Common Stock, and (ii) one director to the Combined Company Board for so long as the TDR Parties beneficially own at least 5%, but less than 15%, of the issued and outstanding shares of Combined Company Common Stock. In connection with such nomination rights, the TDR Parties are subject to certain standstill obligations for so long as Sapphire Holding beneficially owns at least 5% of the issued and outstanding shares of Combined Company Common Stock and certain confidentiality obligations. For more details on the Shareholders Agreement, see the section entitled "The Merger—Voting Agreement and Shareholders Agreement."

Q:

Will the TDR Parties have any limitations on their ability to transfer their shares of Combined Company Common Stock?

A:

Yes. The Shareholders Agreement to be entered into at the Effective Time prohibits Sapphire Holding from transferring its shares of Combined Company Common Stock for six months after the Effective Time. Following such lock-up period, Sapphire Holding will be prohibited from transferring: (i) more than 50% of its shares of Combined Company Common Stock for a period of one year following the end of such lock-up period, (ii) its shares of Combined Company Common Stock to any person or group who beneficially owns more than, or as a result of such transfer, would beneficially own more than, 5% of the then-outstanding shares of Combined Company Common Stock and (iii) until such time that Sapphire Holding beneficially owns less than 5% of the then-outstanding shares of Combined Company Common Stock, more than 2.5% of the then-outstanding shares of Combined Company Common Stock in any 90-day period in an open market sale or block trade, subject to certain exceptions. The Shareholders Agreement will also require Sapphire Holding to transfer its shares of Combined Company Common Stock in accordance with the terms of the Combined Company's securities trading policy.

Q:    Will I still be paid dividends prior to the completion of the Merger?

A:

WillScot has never declared or paid a cash dividend and under the Merger Agreement may not declare or pay any dividends prior to the completion of the Merger. Under the Merger Agreement, Mobile Mini may declare and pay a regular quarterly cash dividend in an amount per share of up to $0.303 per quarter. Mobile Mini is also permitted to declare and pay a special cash dividend prior to the consummation of the Merger in a per share amount equal to the product of (x) $0.303 and (y) a fraction, the numerator of which is the number of days from the first day of

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the calendar quarter in which the consummation of the Merger occurs through such date on which the Merger is completed and the denominator of which is the number of days in such calendar quarter.

For more information regarding the payment of dividends, see the section entitled "The Merger Agreement—Covenants and Agreements."

Q:

When do WillScot and Mobile Mini expect to complete the Merger and the related transactions?

A:

WillScot and Mobile Mini are working to complete the Merger and the related transactions as soon as practicable. WillScot and Mobile Mini currently expect that the Merger and the related transactions will be completed in the third quarter of 2020. Neither WillScot nor Mobile Mini can predict, however, the actual date on which the Merger and the related transactions will be completed because they are subject to conditions beyond each company's control, including obtaining the necessary stockholder and regulatory approvals.

        See the section entitled "The Merger Agreement—Conditions to Completion of the Merger."

Q:    What matters will be considered at each of the special meetings?

A:

WillScot stockholders are being asked to vote on the WillScot Stock Issuance Proposal, the Combined Company Charter Amendment Proposal, the 2020 Incentive Plan Proposal and the WillScot Adjournment Proposal. The approval of the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal are conditions to the obligations of the parties to complete the Merger. The approval of the 2020 Incentive Plan Proposal is not a condition to the obligations of the parties to complete the Merger. See the sections entitled "Questions and Answers About the Merger and the Special Meetings—What vote is required to approve each proposal at the WillScot special meeting?" and "—What happens if the 2020 Incentive Plan Proposal is not approved?"

Mobile Mini stockholders are being asked to vote on the Mobile Mini Merger Proposal, the Mobile Mini Merger-Related Compensation Proposal and the Mobile Mini Adjournment Proposal. The approval of the Mobile Mini Merger Proposal is a condition to the obligations of the parties to complete the Merger. See the section entitled "Questions and Answers About the Merger and the Special Meetings—What vote is required to approve each proposal at the Mobile Mini special meeting?"

Q:    What vote is required to approve each proposal at the WillScot special meeting?

A:

Approval of the WillScot Stock Issuance Proposal requires the affirmative vote of the holders of a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock entitled to vote on the matter at a duly called and held meeting of WillScot stockholders at which a quorum is present (in person or by proxy), voting together as a single class.

Approval of the Combined Company Charter Amendment Proposal requires the affirmative vote of the holders of each of (a) a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock that are entitled to vote, voting together as a single class, (b) a majority of the issued and outstanding shares of WillScot Class A Common Stock, voting as a separate class, and (c) a majority of the issued and outstanding shares of WillScot Class B Common Stock, voting as a separate class.

Approval of the 2020 Incentive Plan Proposal requires the affirmative vote of the majority of shares present in person or by proxy at the meeting and entitled to vote on the matter, voting together as a single class.

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Approval of the WillScot Adjournment Proposal requires that the votes cast in favor of such proposal by the holders of shares of WillScot Common Stock exceed the number of votes cast against such proposal by the holders of shares of WillScot Common Stock.

Q:    What happens if the 2020 Incentive Plan Proposal is not approved?

A:

Approval of the 2020 Incentive Plan Proposal is not a condition to completion of the Merger. Accordingly, if the Merger is approved and the other conditions to closing are satisfied or waived, the Merger will be completed even if the 2020 Incentive Plan Proposal is not approved. If the 2020 Incentive Plan Proposal is not approved, the Combined Company may be required to seek the approval of the stockholders of the Combined Company, prior to the 2021 annual meeting of Combined Company stockholders, to, among other things, increase the number of shares of Combined Company Common Stock authorized for issuance under the WillScot 2017 Incentive Plan and/or to comply with certain post-closing obligations to the management team and certain other employees of the Combined Company as contemplated by the Merger Agreement.

Q:    What vote is required to approve each proposal at the Mobile Mini special meeting?

A:

Approval of the Mobile Mini Merger Proposal requires the affirmative vote of the holders of a majority of the issued and outstanding shares of Mobile Mini Common Stock entitled to vote (in person or by proxy) at the Mobile Mini special meeting.

Approval of the Mobile Mini Merger-Related Compensation Proposal requires the affirmative vote of the holders of a majority of the shares of Mobile Mini Common Stock represented (in person or by proxy) at the Mobile Mini special meeting and entitled to vote on the proposal, assuming a quorum.

Approval of the Mobile Mini Adjournment Proposal requires the affirmative vote of the holders of a majority of the shares of Mobile Mini Common Stock represented (in person or by proxy) at the Mobile Mini special meeting and entitled to vote on the proposal, assuming a quorum.

Q:

Why are Mobile Mini stockholders being asked to consider and vote on a proposal to approve, by advisory (non-binding) vote, the Mobile Mini Merger-Related Compensation?

A:

Under SEC rules, Mobile Mini is required to seek an advisory (non-binding) vote with respect to the compensation that may be paid or become payable to its named executive officers that is based on, or otherwise relates to, the Merger.

Q:    What happens if the Mobile Mini Merger-Related Compensation Proposal is not approved?

A:

Approval of the Mobile Mini Merger-Related Compensation Proposal is not a condition to completion of the Merger, and because the vote on the Mobile Mini Merger-Related Compensation Proposal is advisory only, it will not be binding on Mobile Mini. Accordingly, if the Merger is approved and the other conditions to closing are satisfied or waived, the Merger will be completed even if the Mobile Mini Merger-Related Compensation Proposal is not approved. If the Mobile Mini Merger Proposal is approved by the Mobile Mini stockholders, the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal are approved by the WillScot stockholders and the Merger is completed, the Mobile Mini Merger-Related Compensation will be payable to Mobile Mini's named executive officers, subject only to the conditions applicable thereto, regardless of the outcome of the vote on the Mobile Mini Merger-Related Compensation Proposal.

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Q:

Do any of WillScot's or Mobile Mini's directors or executive officers have interests in the Merger that may differ from those of WillScot stockholders or Mobile Mini stockholders?

A:

WillScot's non-employee directors and executive officers and one of Mobile Mini's non-employee directors (who is Mr. Olsson, who has unvested legacy awards from his tenure as CEO of Mobile Mini; no other non-employee director has equity awards which would vest in connection with the Merger) and executive officers have certain interests in the Merger that may be different from, or in addition to, the interests of WillScot stockholders and Mobile Mini stockholders generally. The WillScot Board was aware of the interests of WillScot's directors and executive officers, the Mobile Mini Board was aware of the interests of Mobile Mini's directors and executive officers, and each board considered such interests, among other matters, when it approved the Merger Agreement and in making its recommendations to its respective stockholders. For more information regarding these interests, see the sections entitled "The Merger—Interests of Certain of WillScot's Directors and Executive Officers in the Merger" and "The Merger—Interests of Mobile Mini's Directors and Executive Officers in the Merger."

Q:    How many votes do I have?

A:

Each WillScot stockholder is entitled to one vote for each share of WillScot Common Stock held of record as of the WillScot Record Date and each Mobile Mini stockholder is entitled to one vote for each share of Mobile Mini Common Stock held of record as of the Mobile Mini Record Date.

As of the close of business on [                ], 2020, there were [                ] shares of WillScot Class A Common Stock and                 shares of WillScot Class B Common Stock outstanding. As of the close of business on [                ], 2020, there were [                ] shares of Mobile Mini Common Stock outstanding. As summarized below, there are some important distinctions between shares held of record and those owned beneficially in street name.

Q:    What constitutes a quorum for the WillScot special meeting?

The holders of a majority of the outstanding shares of WillScot Common Stock as of the WillScot Record Date, present either in person or by proxy and entitled to vote at the meeting, will constitute a quorum for the transaction of business at the WillScot special meeting. Abstentions (which are described below) will count for the purpose of determining the presence of a quorum for the transaction of business at the WillScot special meeting.

Q:    What constitutes a quorum for the Mobile Mini special meeting?

The holders of a majority of the outstanding shares of Mobile Mini Common Stock as of the Mobile Mini Record Date entitled to vote, represented in person or by proxy, will constitute a quorum for the transaction of business at the Mobile Mini special meeting. Abstentions (which are described below) will count for the purpose of determining the presence of a quorum for the transaction of business at the Mobile Mini special meeting.

Q:    How does the WillScot Board recommend that WillScot stockholders vote?

A:

The WillScot Board unanimously recommends that WillScot stockholders vote: "FOR" the WillScot Stock Issuance Proposal, "FOR" the Combined Company Charter Amendment Proposal, "FOR" the 2020 Incentive Plan Proposal and "FOR" the WillScot Adjournment Proposal.

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Q:    How does the Mobile Mini Board recommend that Mobile Mini stockholders vote?

A:

The Mobile Mini Board recommends that Mobile Mini stockholders vote: "FOR" the Mobile Mini Merger Proposal, "FOR" the Mobile Mini Merger-Related Compensation Proposal and "FOR" the Mobile Mini Adjournment Proposal.

Q:

Why did the WillScot Board approve the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger?

A:

For information regarding the WillScot Board's reasons for approving the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, and recommending that WillScot stockholders approve the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal, see the section entitled "The Merger—WillScot Board's Recommendation and Reasons for the Merger."

Q:

Why did the Mobile Mini Board approve the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger?

A:

For information regarding the Mobile Mini Board's reasons for approving and recommending adoption of the Merger Agreement and the transactions contemplated by the Merger Agreement, including the Merger, see the section entitled "The Merger—Mobile Mini Board's Recommendation and Reasons for the Merger."

Q:

What if I hold shares in both WillScot and Mobile Mini?

A:

If you hold shares of both WillScot Common Stock and Mobile Mini Common Stock, you will receive two separate packages of proxy materials. A vote cast as a holder of WillScot Common Stock will not count as a vote cast as a holder of Mobile Mini Common Stock, and a vote cast as a holder of Mobile Mini Common stock will not count as a vote cast as a holder of WillScot Common Stock. Therefore, please submit separate proxies for your shares of WillScot Common Stock and your shares of Mobile Mini Common Stock.

Q:

What do I need to do now?

A:

After carefully reading and considering the information contained in this joint proxy statement/prospectus, please vote your shares as soon as possible so that your shares will be represented at the WillScot special meeting or Mobile Mini special meeting, as applicable. Please follow the instructions set forth on the WillScot proxy card or the Mobile Mini proxy card, as applicable, or on the voting instruction form provided by the record holder if your shares are held in the name of your bank, broker or other nominee.

If you are a Mobile Mini stockholder and hold your shares in certificated form, please do not submit your stock certificates at this time. If the Merger is completed, you will receive instructions for surrendering your stock certificates from the exchange agent.

Q:    Does my vote matter?

A:

Yes. The Merger cannot be completed without approval of the WillScot Stock Issuance Proposal, the Combined Company Charter Amendment Proposal and the Mobile Mini Merger Proposal. WillScot stockholders will need to approve:

•

the WillScot Stock Issuance Proposal by the affirmative vote of the holders of a majority of the issued and outstanding shares of WillScot Common Stock entitled to vote on the matter at a duly called and held meeting of WillScot stockholders at which a quorum is present (in person or by proxy) at the WillScot special meeting;

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the Combined Company Charter Amendment Proposal by the affirmative vote of the holders of each of:



•

a majority of the issued and outstanding shares of WillScot Class A Common Stock and WillScot Class B Common Stock that are entitled to vote, voting together as a single class,



•

a majority of the issued and outstanding shares of WillScot Class A Common Stock, voting as a separate class, and



•

a majority of the issued and outstanding shares of WillScot Class B Common Stock, voting as a separate class.

The Mobile Mini stockholders will need to approve:

•

the Mobile Mini Merger Proposal by the affirmative vote of the holders of a majority of the issued and outstanding shares of Mobile Mini Common Stock entitled to vote (in person or by proxy) at the Mobile Mini special meeting.

Q:    How do I vote?

A:

If you are a stockholder of record of WillScot as of the WillScot Record Date, you are entitled to receive notice of, and cast a vote at, the WillScot special meeting. If you are a stockholder of record of Mobile Mini as of the Mobile Mini Record Date, you are entitled to receive notice of, and cast a vote at, the Mobile Mini special meeting. Each holder of WillScot Common Stock is entitled to cast one vote on each matter properly brought before the WillScot special meeting for each share of WillScot Common Stock that such holder owned of record as of the WillScot Record Date. Each holder of Mobile Mini common stock is entitled to cast one vote on each matter properly brought before the Mobile Mini special meeting for each share of Mobile Mini Common Stock that such holder owned of record as of the Mobile Mini Record Date. You may submit your proxy before the WillScot special meeting or the Mobile Mini special meeting, as applicable, in one of the following ways:

•

Telephone voting-use the toll-free number shown on your proxy card;

•

Via the Internet-visit the website shown on your proxy card to vote via the Internet; or

•

Mail-complete, sign, date and return the enclosed proxy card in the enclosed postage-paid envelope.

If you are a stockholder of record, you may also cast your vote in person via live webcast at the applicable special meeting.

If your shares are held in "street name," through a bank, broker or other nominee, that institution will send you separate instructions describing the procedure for voting your shares. "Street name" stockholders who wish to vote at the WillScot special meeting or the Mobile Mini special meeting should follow the instructions provided by their bank, broker or other nominee.

Q:

What is the difference between holding shares as a stockholder of record and as a beneficial owner?

A:

You are a "stockholder of record" if your shares are registered directly in your name with WillScot's transfer agent, Continental Stock Transfer & Trust Company ("Continental"), or Mobile Mini's transfer agent Broadridge Corporate Issuer Solutions, Inc. ("Broadridge Corporate Issuer Solutions"), as applicable. As the stockholder of record, you have the right to vote in person via live webcast at the WillScot special meeting or the Mobile Mini special meeting, as applicable. You may also vote by Internet, telephone or mail, as described in the notice and above under the

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heading "How do I vote?" You are deemed to beneficially own shares in "street name" if your shares are held by a bank, broker or other nominee. Your bank, broker or other nominee will send you, as the beneficial owner, a package describing the procedure for voting your shares. You should follow the instructions provided by them to vote your shares. If you beneficially own your shares, you are invited to attend the WillScot special meeting or Mobile Mini special meeting, as applicable.

Q:

If my shares are held in "street name" by a bank, broker or other nominee, will my bank, broker or other nominee vote my shares for me?

A:

If your shares are held in "street name" by a bank, broker or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your bank, broker or other nominee. Please note that you may not vote shares held in street name by returning a proxy card directly to WillScot or Mobile Mini, as applicable, or by voting in person via live webcast at the WillScot special meeting or Mobile Mini special meeting, as applicable, unless you provide a "legal proxy," which you must obtain from your bank, broker or other nominee. Your bank, broker or other nominee is obligated to provide you with a voting instruction card for you to use.

Banks, brokers or other nominees who hold shares in street name for a beneficial owner of those shares typically have the authority to vote in their discretion on "routine" proposals when they have not received instructions from beneficial owners. However, banks, brokers or other nominees are not allowed to exercise their voting discretion with respect to the approval of matters determined to be "non-routine" without specific instructions from the beneficial owner. It is expected that all proposals to be voted on at each of the WillScot special meeting and the Mobile Mini special meeting are "non-routine" matters. Broker non-votes occur when a broker or nominee is not instructed by the beneficial owner of shares to vote on a particular proposal for which the bank, broker or other nominee does not have discretionary voting power.

If you are a beneficial owner of WillScot shares and you do not instruct your bank, broker or other nominee on how to vote your shares:

•

your bank, broker or other nominee may not vote your shares on the WillScot Stock Issuance Proposal, which broker non-votes, if any, will have the same effect as a vote "AGAINST" such proposal;



•

your bank, broker or other nominee may not vote your shares on the Combined Company Charter Amendment Proposal, which broker non-votes, if any, will have the same effect as a vote "AGAINST" such proposal;



•

your bank, broker or other nominee may not vote your shares on the 2020 Incentive Plan Proposal, which broker non-votes, if any, will have no effect on the outcome of such proposal; and



•

your bank, broker or other nominee may not vote your shares on the WillScot Adjournment Proposal, which broker non-votes, if any, will have no effect on the outcome of such proposal.

If you are a beneficial owner of Mobile Mini shares and you do not instruct your bank, broker or other nominee on how to vote your shares:

•

your bank, broker or other nominee may not vote your shares on the Mobile Mini Merger Proposal, which broker non-votes, if any, will have the same effect as a vote "AGAINST" such proposal;

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your bank, broker or other nominee may not vote your shares on the Mobile Mini Merger-Related Compensation Proposal, which broker non-votes, if any, will have no effect on the outcome of such proposal; and



•

your bank, broker or other nominee may not vote your shares on the Mobile Mini Adjournment Proposal, which broker non-votes, if any, will have no effect on the outcome of such proposal.

Q:    May I attend the WillScot special meeting or the Mobile Mini special meeting in person?

Each of WillScot and Mobile Mini has chosen to hold its special meeting solely via the Internet and not in a physical location given the current public health impact of coronavirus (COVID-19) and the desire to promote the health and safety of its stockholders, as well as its directors, officers, employees and other constituents.

You or your authorized proxy may attend the WillScot special meeting in person via live webcast if you were a registered or beneficial stockholder of WillScot Common Stock as of the WillScot Record Date.

You or your authorized proxy may attend the Mobile Mini special meeting in person via live webcast if you were a registered or beneficial stockholder of Mobile Mini Common Stock as of the Mobile Mini Record Date.

Q:

When and where will each of the WillScot special meeting and Mobile Mini special meeting take place?

The WillScot special meeting will be held exclusively via live webcast through the link [            ] at [            ] on [            ], 2020 at [            ] a.m. Eastern Time. There will not be a physical meeting location. The WillScot special meeting can be accessed by visiting [            ], where you will be able to attend the WillScot special meeting, vote and submit your questions. WillScot has chosen to hold the WillScot special meeting solely via live webcast and not in a physical location given the current public health impact of COVID-19 and its desire to promote the health and safety of WillScot stockholders, as well as WillScot directors, officers, employees and other constituents.

To attend the WillScot special meeting, you will need the 16-digit control number included on your proxy card if you are a stockholder of record or included with your voting instruction form provided by your bank, broker or other nominee if you hold your shares of WillScot Common Stock in street name through an account with an intermediary.

You may log into the WillScot special meeting website and enter your control number beginning fifteen (15) minutes before the commencement of the WillScot special meeting. Instructions on how to attend and participate online at the WillScot special meeting, including how to demonstrate proof of stock ownership, ask questions and vote, are posted at [            ].

The Mobile Mini special meeting will be held exclusively via live webcast through the link [            ] at [            ] on [            ], 2020 at [            ] a.m. Phoenix local time. There will not be a physical meeting location. The Mobile Mini special meeting can be accessed by visiting [            ], where you will be able to attend the Mobile Mini special meeting, vote and submit your questions. Mobile Mini has chosen to hold the Mobile Mini special meeting solely via live webcast and not in a physical location given the current public health impact of COVID-19 and its desire to promote the health and safety of Mobile Mini stockholders, as well as Mobile Mini directors, officers, employees and other constituents.

To attend the Mobile Mini special meeting, you will need the 16-digit control number included on your proxy card if you are a stockholder of record or included with your voting instruction form provided by your bank, broker or other nominee if you hold your shares of Mobile Mini Common Stock in street name through an account with an intermediary.

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You may log into the Mobile Mini special meeting website and enter your control number beginning fifteen (15) minutes before the commencement of the Mobile Mini special meeting. Instructions on how to attend and participate online at the Mobile Mini special meeting, including how to demonstrate proof of stock ownership, ask questions and vote, are posted at [            ].

Q:    What if I fail to vote or abstain?

A:

For purposes of the WillScot special meeting, an abstention occurs when a WillScot stockholder attends the WillScot special meeting in person via live webcast and abstains from voting or returns a proxy with an "abstain" instruction.

An abstention on the WillScot Stock Issuance Proposal will have the same effect as a vote cast "AGAINST" the WillScot Stock Issuance Proposal. If a WillScot stockholder is not present in person via live webcast at the WillScot special meeting and does not respond by proxy, it will have the same effect as a vote cast "AGAINST" such proposal.

An abstention on the Combined Company Charter Amendment Proposal will have the same effect as a vote cast "AGAINST" the Combined Company Charter Amendment Proposal. If a WillScot stockholder is not present in person via live webcast at the WillScot special meeting and does not respond by proxy, it will have the same effect as a vote cast "AGAINST" such proposal.

An abstention on the 2020 Incentive Plan Proposal will have the same effect as a vote cast "AGAINST" the 2020 Incentive Plan Proposal. If a WillScot stockholder is not present in person via live webcast at the WillScot special meeting and does not respond by proxy, it will have no effect on the vote count for such proposal.

An abstention on the WillScot Adjournment Proposal will have no effect on the WillScot Adjournment Proposal. If a WillScot stockholder is not present in person via live webcast at the WillScot special meeting and does not respond by proxy, it will have no effect on the vote count for such proposal.

For purposes of the Mobile Mini special meeting, an abstention occurs when a Mobile Mini stockholder attends the Mobile Mini special meeting in person via live webcast and does not vote or returns a proxy with an "abstain" instruction.

An abstention on the Mobile Mini Merger Proposal will have the same effect as a vote cast "AGAINST" the Mobile Mini Merger Proposal. If a Mobile Mini stockholder is not present in person via live webcast at the Mobile Mini special meeting and does not respond by proxy, it will have the same effect of a vote cast "AGAINST" such proposal.

An abstention on the Mobile Mini Merger-Related Compensation Proposal will have the same effect as a vote cast "AGAINST" the Mobile Mini Merger-Related Compensation Proposal. If a Mobile Mini stockholder is not present in person via live webcast at the Mobile Mini special meeting and does not respond by proxy, it will have no effect on the outcome of the Mobile Mini Merger-Related Compensation Proposal.

An abstention on the Mobile Mini Adjournment Proposal will have the same effect as a vote cast "AGAINST" the Mobile Mini Adjournment Proposal. If a Mobile Mini stockholder is not present in person via live webcast at the Mobile Mini special meeting and does not respond by proxy, it will have no effect on the vote count for such proposal.

Q:

What will happen if I return my proxy or voting instruction card without indicating how to vote?

A:

If you sign and return your proxy or voting instruction card without indicating how to vote on any particular proposal, the common stock represented by your proxy will be voted as recommended by the WillScot Board or the Mobile Mini Board, as applicable, with respect to that proposal.

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Q:    May I change or revoke my vote after I have delivered my proxy or voting instruction card?

A:

Yes. If you are a record holder, you may change or revoke your vote before your proxy is voted at the WillScot special meeting or the Mobile Mini special meeting, as applicable, as described herein. You may do this in one of the following four ways:

•

by logging onto the Internet website specified on your proxy card in the same manner you would to submit your proxy electronically or by calling the telephone number specified on your proxy card, in each case, if you are eligible to do so;

•

by sending a notice of revocation to the Corporate Secretary of WillScot or Mobile Mini, as applicable;

•

by sending a completed proxy card bearing a later date than your original proxy card; or

•

by attending the WillScot special meeting or the Mobile Mini special meeting, as applicable, and voting in person via live webcast.

If you choose any of the first three methods, you must take the described action no later than the beginning of the WillScot special meeting or the Mobile Mini special meeting, as applicable.

If your shares are held in an account at a bank, broker or other nominee and you have delivered your voting instruction card or otherwise given instruction on how to vote your shares to your bank, broker or other nominee or your applicable plan administrator, you should contact your bank, broker or other nominee or your applicable plan administrator to change your vote.

Q:    What are the material U.S. federal income tax consequences of the Merger?

A:

It is a condition to each party's obligation to complete the Merger that each of WillScot and Mobile Mini receive an opinion of its respective outside counsel to the effect that the Merger will qualify as a "reorganization" within the meaning of Section 368(a) of the Code. Accordingly, it is expected that U.S. holders of shares of Mobile Mini Common Stock generally will not recognize any gain or loss for U.S. federal income tax purposes upon receipt of WillScot Class A Common Stock in exchange for Mobile Mini Common Stock in the Merger (other than gain or loss, if any, with respect to any cash received in lieu of a fractional share of WillScot Class A Common Stock). Neither Mobile Mini nor WillScot will recognize any gain or loss for U.S. federal income tax purposes as a result of the Merger.

Mobile Mini stockholders should consult their own tax advisors as to the particular consequences to them of the Merger, including the applicability and effect of any U.S. federal, state and local tax laws, as well as foreign tax laws. For more information regarding the material U.S. federal income tax consequences of the Merger, see "The Merger—Material U.S. Federal Income Tax Consequences of the Merger."

Q:

Where can I find the voting results of the WillScot special meeting and the Mobile Mini special meeting?

A:

The preliminary voting results will be announced at each of the WillScot special meeting and the Mobile Mini special meeting. In addition, within four business days following certification of the final voting results, each of WillScot and Mobile Mini intends to file the final voting results with the SEC on a Current Report on Form 8-K.

Q:    Are holders of WillScot Common Stock entitled to appraisal rights?

A:

No. Holders of WillScot Common Stock are not entitled to appraisal rights under the DGCL. For more information, see the section entitled "The Merger—No Appraisal Rights in the Merger."

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Q:    Are holders of Mobile Mini Common Stock entitled to appraisal rights?

A:

No. Holders of Mobile Mini Common Stock are not entitled to appraisal rights under the DGCL. For more information, see the section entitled "The Merger—No Appraisal Rights in the Merger."

Q:

What happens if I sell my shares of WillScot Common Stock after the WillScot record date but before the WillScot special meeting?

A:

The WillScot Record Date for the WillScot special meeting (the close of business on [            ], 2020) is earlier than the date of the WillScot special meeting and earlier than the date that the Merger is expected to be completed. If you sell or otherwise transfer your shares of WillScot Common Stock after the WillScot Record Date but before the date of the WillScot special meeting, you will retain your right to vote at the WillScot special meeting.

Q:

What happens if I sell my shares of Mobile Mini Common Stock after the Mobile Mini record date but before the Mobile Mini special meeting?

A:

The Mobile Mini Record Date for the Mobile Mini special meeting (the close of business on [            ], 2020) is earlier than the date of the Mobile Mini special meeting and earlier than the date that the Merger is expected to be completed. If you sell or otherwise transfer your shares of Mobile Mini Common Stock after the Mobile Mini Record Date but before the date of the Mobile Mini special meeting, you will retain your right to vote at the Mobile Mini special meeting. However, you will not have the right to receive the Merger Consideration to be received by Mobile Mini stockholders in the Merger. In order to receive the Merger Consideration, you must hold your shares through completion of the Merger.

Q:

Are there any risks that I should consider in deciding whether to vote in favor of the WillScot Proposals or the Mobile Mini Proposals to be considered at the WillScot special meeting or the Mobile Mini special meeting, as applicable?

A:

Yes. You should read and carefully consider the risk factors set forth in the section entitled "Risk Factors" beginning on page 30. You also should read and carefully consider the risk factors of WillScot and Mobile Mini contained in the documents that are incorporated by reference into this joint proxy statement/prospectus.

Q:    What are the conditions to completion of the Merger?

A:

In addition to the approval of the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal by WillScot stockholders and of the Mobile Mini Merger Proposal by Mobile Mini stockholders as described above, completion of the Merger is subject to the satisfaction or (to the extent permitted by law) waiver of a number of other conditions, including:

•

the expiration or termination of the applicable waiting period under the HSR Act without the imposition of a regulatory adverse effect;

•

the effectiveness of the registration statement on Form S-4 of which this joint proxy statement/prospectus forms a part;

•

approval of the listing on Nasdaq of the shares of WillScot Class A Common Stock forming the Merger Consideration, which will be reclassified as and converted into shares of Combined Company Common Stock at the Effective Time;

•

the absence of any law, injunction, judgment, order, decree or other legal restraint or prohibition preventing the consummation of the Merger or any of the other transactions contemplated by the Merger Agreement and the ancillary agreements;

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receipt by each of WillScot and Mobile Mini of an opinion of its respective outside counsel to the effect that the Merger will qualify as a "reorganization" within the meaning of Section 368(a) of the Code;



•

the debt financing contemplated by the Commitment Letter (as defined below) entered into by WillScot in connection with the Merger having been obtained;



•

in the case of Mobile Mini, the completion of the exchange by Sapphire Holding of its shares of WSHC Stock for shares of WillScot Class A Common Stock pursuant to the Voting Agreement, and the concurrent cancellation of all issued and outstanding WillScot Class B Common Stock;



•

the accuracy of the representations and warranties of WillScot or Mobile Mini, as applicable, made in the Merger Agreement (subject to the materiality standards set forth in the Merger Agreement);



•

the absence of a material adverse effect with respect to WillScot or Mobile Mini since the date of the Merger Agreement;



•

the performance by WillScot or Mobile Mini, as applicable, of its covenants and obligations under the Merger Agreement in all material respects; and



•

delivery of an officer certificate by the other party certifying satisfaction of, among other things, the applicable conditions described in the preceding four bullet points.

See the section entitled "The Merger Agreement—Conditions to Completion of the Merger" for additional information.

Q:    Whom should I contact if I have any questions about the proxy materials or voting?

A:

If you have any questions about the proxy materials, or if you need assistance submitting your proxy or voting your shares or need additional copies of this joint proxy statement/prospectus or the enclosed WillScot proxy card or Mobile Mini proxy card, as applicable, you should contact Georgeson LLC, the proxy solicitation agent for WillScot, at 866-785-7395 (toll-free) or 781-575-2137 (for all those outside of the U.S.) or Innisfree M&A Incorporated, the proxy solicitation agent for Mobile Mini, at (877) 800-5195 (toll-free) or (212) 750-5833 (collect), as applicable.

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SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF WILLSCOT

        The following table presents selected historical consolidated financial data for WillScot as of and for the years ended December 31, 2019, 2018, 2017, 2016 and 2015. The statement of operations data and cash flow data for the years ended December 31, 2019, 2018 and 2017 and the balance sheet data as of December 31, 2019 and 2018 have been obtained from WillScot's audited consolidated financial statements incorporated by reference in WillScot'sAnnual Report on Form 10-K for the year ended December 31, 2019 (the "WillScot 10-K"), which is incorporated by reference into this joint proxy statement/prospectus. The statement of operations data for the years ended December 31, 2016 and 2015 and the balance sheet data as of December 31, 2017, 2016 and 2015 have been derived from WillScot's audited consolidated financial statements for such years, which have not been incorporated by reference into this joint proxy statement/prospectus.

        WillScot was incorporated under the name Double Eagle Acquisition Corporation ("Double Eagle") on June 26, 2015. Prior to November 29, 2017, Double Eagle was a Nasdaq-listed special purpose acquisition company formed for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination. On November 29, 2017, Double Eagle indirectly acquired Williams Scotsman International, Inc. ("WSII") from Algeco Scotsman Global S.à r.l. (together with its subsidiaries, the "Algeco Group"), which is majority-owned by an investment fund managed by TDR Capital. As part of the transaction (the "2017 Business Combination"), Double Eagle domesticated to Delaware and changed its name to WillScot Corporation.

        The 2017 Business Combination was accounted for as a reverse acquisition in which WSII was the accounting acquirer. Except as otherwise provided herein, WillScot's financial statement presentation includes (i) the results of WSII and its subsidiaries as WillScot's accounting predecessor for periods prior to the completion of the 2017 Business Combination, and (ii) the results of WillScot (including the consolidation of WSII and its subsidiaries) for periods after the completion of the 2017 Business Combination. The operating statistics and data contained herein represent the operating information of WSII's business.

        On August 15, 2018, WSII acquired Modular Space Holdings, Inc. ("ModSpace"). Results of operations from ModSpace subsequent to the acquisition date are included in WillScot's consolidated operating results. Lease fleet and all other assets acquired and liabilities assumed in the transaction are included in WillScot's balance sheet for all periods following the acquisition. Certain historical financial statements of ModSpace are incorporated by reference into this joint proxy statement/prospectus.

        At December 31, 2019, WillScot became a large accelerated filer and no longer qualifies as an emerging growth company, at which point WillScot was required to retrospectively adopt ASC 842, effective January 1, 2019. In connection with the adoption of ASC 842, WillScot reversed the previous accounting for certain failed sale-leaseback transactions, and reduced property, plant and equipment by $31.0 million, reduced outstanding debt by $37.9 million, increased deferred tax liability by $1.8 million and increased January 1, 2019 equity by $5.2 million. WillScot recognized lease liabilities and ROU assets of $138.5 million and $141.4 million as of January 1, 2019, primarily related to its real estate and equipment leases.

        The adoption of ASC 842 at January 1, 2019, did not have a significant impact on the recognition of leasing revenue. Per the requirements of ASC 842 WillScot records changes in estimated collectibility, directly against lease income. Such amounts were previously classified as selling, general and administrative expenses. For the year ended December 31, 2019 operating lease receivables not deemed probable of collection and recorded as a reduction of revenue totaled $10.0 million.

        The historical consolidated financial data for 2017 includes the significant impact of the enactment of the Tax Cuts and Jobs Act (the "Tax Act"). The historical consolidated financial data for 2019 and 2018 reflect a lower effective tax rate than the years prior to the enactment of the Tax Act. The Tax Act reduced the U.S. federal statutory tax rate from 35% to 21%.

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        The information set forth below is not necessarily indicative of future results and should be read together with the other information contained in the WillScot 10-K, including the section entitled "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the consolidated financial statements and related notes therein. See the section entitled "Where You Can Find More Information."

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SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF MOBILE MINI

        The following table presents selected historical consolidated financial data for Mobile Mini as of and for the years ended December 31, 2019, 2018, 2017, 2016 and 2015. The statement of operations data and cash flow data for the years ended December 31, 2019, 2018 and 2017 and the balance sheet data as of December 31, 2019 and 2018 have been obtained from Mobile Mini's audited consolidated financial statements included in Mobile Mini'sAnnual Report on Form 10-K for the year ended December 31, 2019 (the "Mobile Mini 10-K"), which is incorporated by reference into this joint proxy statement/prospectus. The statement of operations data and cash flow data for the year ended December 31, 2016 and 2015 and the balance sheet data as of December 31, 2017, 2016 and 2015 have been derived from Mobile Mini's audited consolidated financial statements for such year, which have not been incorporated by reference into this joint proxy statement/prospectus.

        The information set forth below is not necessarily indicative of future results and should be read together with the other information contained in the Mobile Mini 10-K, including the sections entitled "Management's Discussion and Analysis of Financial Condition and Results of Operations" and the

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consolidated financial statements and related notes therein. See the section entitled "Where You Can Find More Information."

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SELECTED UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

        The following table shows selected unaudited pro forma condensed combined financial information about the financial condition and results of operations of the Combined Company after giving effect to the Merger and related transactions as described in the section entitled "Unaudited Pro Forma Condensed Combined Financial Information." The selected unaudited pro forma condensed combined balance sheet data as of December 31, 2019 give effect to the Merger and related transactions as if they occurred on December 31, 2019. The selected unaudited pro forma condensed combined statement of operations data for the year ended December 31, 2019 give effect to the transactions as if they occurred on January 1, 2019, the first day of WillScot's 2019 fiscal year.

        The selected pro forma data have been derived from, and should be read in conjunction with, the more detailed unaudited pro forma condensed combined financial information of the Combined Company appearing elsewhere in this joint proxy statement/prospectus and the accompanying notes to the pro forma financial information. Additionally, the unaudited pro forma condensed combined financial information contains estimated adjustments, based upon available information and certain assumptions that we believe are reasonable under the circumstances. The assumptions underlying the pro forma adjustments are described in greater detail in the section entitled "Notes to Unaudited Pro Forma Condensed Combined Financial Information." In addition, the pro forma financial information were based on, and should be read in conjunction with, the historical consolidated financial statements and related notes of WillScot and Mobile Mini for the applicable periods, which have been incorporated in this joint proxy statement/prospectus by reference. See the sections entitled "Unaudited Pro Forma Condensed Combined Financial Information" and "Where You Can Find More Information" for additional information.

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COMPARATIVE PER SHARE MARKET PRICE INFORMATION

        The following table sets forth the closing price per share of WillScot Class A Common Stock and Mobile Mini Common Stock, in each case, as reported on Nasdaq on February 28, 2020, the last trading day prior to public announcement of the Merger by WillScot and Mobile Mini, and on April 30, 2020, the most recent practicable trading day prior to the date of this joint proxy statement/prospectus for which this information was available. The table also shows the implied value of the Merger Consideration for each share of Mobile Mini Common Stock as of the same dates. This implied value was calculated by multiplying the closing price of a share of WillScot Class A Common Stock on the relevant date by the Exchange Ratio.

        The market prices of shares of WillScot Class A Common Stock and Mobile Mini Common Stock have fluctuated since the date of the announcement of the Merger and may continue to fluctuate from the date of this joint proxy statement/prospectus to the dates of the WillScot special meeting, the Mobile Mini special meeting and the date the Merger is completed. No assurance can be given concerning the market prices of shares of WillScot Class A Common Stock and shares of Mobile Mini Common Stock before completion of the Merger or shares of Combined Company Common Stock after completion of the Merger. The Exchange Ratio is fixed at 2.4050 in the Merger Agreement, but the market price of shares of WillScot Class A Common Stock (and therefore the value of the Merger Consideration) when received by Mobile Mini stockholders at the Effective Time could be greater than, less than or the same as shown in the table above. Accordingly, these comparisons may not provide meaningful information to WillScot stockholders and Mobile Mini stockholders in determining how to vote with respect to the proposals described in this joint proxy statement/prospectus. WillScot stockholders and Mobile Mini stockholders are advised to obtain current market quotations for WillScot Class A Common Stock and Mobile Mini Common Stock and to review carefully the other information contained in this joint proxy statement/prospectus or incorporated by reference into this joint proxy statement/prospectus. For more information, see the section entitled "Where You Can Find More Information" beginning on page 260 of this joint proxy statement/prospectus.

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COMPARATIVE HISTORICAL AND UNAUDITED PRO FORMA PER SHARE DATA

        The following table summarizes per share data (1) for WillScot and Mobile Mini on a historical basis, (2) for the Combined Company on an unaudited pro forma combined basis giving effect to the Merger and related transactions and (3) on an unaudited pro forma combined equivalent basis.

        The unaudited pro forma income from continuing operations per share for the year ended December 31, 2019 reflects the transactions as if they had occurred on January 1, 2019. The book value per share reflects the transactions as if they had occurred on December 31, 2019. The information in the table is based on, and should be read together with, the historical financial information of WillScot and Mobile Mini which is incorporated by reference in this joint proxy statement/prospectus and the financial information contained under "Unaudited Pro Forma Condensed Combined Financial Information," "Selected Historical Consolidated Financial Data of WillScot" and "Selected Historical Consolidated Financial Data of Mobile Mini." See the section entitled "Where You Can Find More Information."

        The unaudited pro forma combined per share data is presented for illustrative purposes only and is not necessarily indicative of actual or future financial position or results of operations that would have been realized if the transactions had been completed as of the dates indicated or will be realized upon the completion of the transactions. The summary pro forma information is preliminary, based on initial estimates of the fair value of assets acquired (including intangible assets) and liabilities assumed, and is subject to change as more information regarding the fair values are obtained, which changes could be materially different than the initial estimates.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This joint proxy statement/prospectus contains statements which, to the extent they are not statements of historical or present fact, constitute "forward-looking statements" under the securities laws. From time to time, oral or written forward-looking statements may also be included in other information released to the public. These forward-looking statements are intended to provide Mobile Mini's and WillScot's respective management's current expectations or plans for WillScot's or the Combined Company's future operating and financial performance, based on assumptions currently believed to be valid. The words "estimates," "expects," "anticipates," "believes," "forecasts," "projects," "plans," "intends," "may," "will," "should," "could," "shall," "continue," "outlook" and variations of these words and similar expressions (or the negative thereof) identify forward-looking statements, which are generally not historical in nature. Certain of these forward-looking statements relate to the Merger involving WillScot and Mobile Mini, including: expected scale; operating efficiency; stockholder, employee and customer benefits; key assumptions; timing of closing; the amount and timing of revenue and expense synergies; future financial benefits and operating results; and integration spend, which reflects management's beliefs, expectations and objectives as of the date hereof. All forward-looking statements involve risks, uncertainties and other factors that may cause actual results to differ materially from those expressed or implied in the forward-looking statements. For those statements, we claim the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995. Such risks, uncertainties and other factors include, without limitation:

•

negative effects of the announcement or pendency of the Merger on the market price of WillScot's and/or Mobile Mini's respective common stock and/or on their respective financial performance;



•

the ability of the parties to receive the required regulatory approvals for the Merger (and the risk that such approvals may result in the imposition of conditions that could adversely affect the Combined Company or the expected benefits of the transaction) and approvals of WillScot's stockholders and Mobile Mini's stockholders and to satisfy the other conditions to the completion of the Merger on a timely basis or at all;



•

the occurrence of events that may give rise to a right of one or both of the parties to terminate the Merger Agreement;



•

risks relating to the value of the WillScot shares to be issued in the Merger, significant transaction costs and/or unknown liabilities;



•

the possibility that the anticipated benefits, including cost synergies, from the Merger cannot be realized in full or at all or may take longer to realize than expected, including risks associated with third-party contracts containing consent and/or other provisions that may be triggered by the proposed transaction;



•

risks associated with transaction-related litigation;



•

the possibility that costs or difficulties related to the integration of WillScot's and Mobile Mini's operations will be greater than expected or that the integration plan will not be successfully implemented;



•

the ability of WillScot and Mobile Mini to manage growth and execute their business plan, the rate and degree of market acceptance of their products and the success of other competing modular space and portable solutions that exist or may become available;



•

the ability of each of Mobile Mini, WillScot and the Combined Company to retain and hire key personnel;

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•

the intended qualification of the Merger as a tax-free reorganization for U.S. federal income tax purposes;



•

expected financing transactions undertaken in connection with the Merger;



•

the impact of the Merger on the respective businesses of Mobile Mini and WillScot and the risk that the Merger may be more difficult, time-consuming or costly than expected, including the impact on relationships of the Combined Company with customers, suppliers, employees and other business counterparties;



•

the scope, nature, impact or timing of the Merger and other merger, acquisition and divestiture activity, including among other things the integration of or with other businesses;



•

the effect of economic conditions in the industries and markets in which WillScot and Mobile Mini operate in the United States and globally and any changes therein, including financial market conditions, fluctuations in commodity prices, interest rates and foreign currency exchange rates, levels of end market demand in construction, the impact of weather conditions and natural disasters, the impact of the global pandemic related to COVID-19 and the financial condition of WillScot's and Mobile Mini's customers and suppliers;



•

future availability of credit and factors that may affect such availability, including credit market conditions and capital structure;



•

delays and disruption in delivery of materials and services from suppliers;



•

new business and investment opportunities;



•

the diversion of management attention from business operations to the proposed transaction;



•

the ability to realize the intended benefits of organizational changes;



•

risks associated with indebtedness;



•

the anticipated benefits of diversification and balance of operations across product lines, regions and industries;



•

the outcome of legal proceedings, investigations and other contingencies;



•

the inherent uncertainty associated with financial or other projections;



•

the impact of the negotiation of collective bargaining agreements and labor disputes;



•

the effect of changes in political conditions in the U.S. and other countries in which WillScot, Mobile Mini and the businesses of each operate, including the effect of changes in U.S. trade policies or the United Kingdom's withdrawal from the European Union, on general market conditions, global trade policies and currency exchange rates in the near term and beyond;



•

the effect of changes in tax, environmental, regulatory and other laws and regulations (including, among other things, anti-bribery and anti-corruption requirements, including the Foreign Corrupt Practices Act, industrial cooperation agreement obligations, and procurement and other regulations) in the United States and other countries in which WillScot, Mobile Mini and the businesses of each operate;



•

risks relating to completed acquisitions and divestiture activities and the risk that the integration of such acquisitions may be more difficult, time-consuming or costly than expected; and



•

other risk factors as detailed from time to time in WillScot's and Mobile Mini's reports filed with the SEC, including WillScot's and Mobile Mini's respective annual reports on Form 10-K, periodic current reports on Form 8-K and other documents filed with the SEC, including the

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risks and uncertainties set forth in or incorporated by reference into this joint proxy statement/prospectus in the section entitled "Risk Factors."

        There can be no assurance that the Merger or any other transaction described in this joint proxy statement/prospectus will in fact be completed in the manner described or at all. Any forward-looking statement speaks only as of the date on which it is made, and WillScot and Mobile Mini assume no obligation to update or revise such statement, whether as a result of new information, future events or otherwise, except as required by applicable law. Readers are cautioned not to place undue reliance on any of these forward-looking statements.

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RISK FACTORS

        In addition to the other information contained or incorporated by reference into this joint proxy statement/prospectus, including the matters addressed in "Cautionary Note Regarding Forward-Looking Statements" beginning on page 27 of this joint proxy statement/prospectus, you should carefully consider the following risk factors in determining whether to vote in favor of the Mobile Mini Proposals or the WillScot Proposals, as applicable. You should also read and consider the risk factors associated with each of the businesses of WillScot and Mobile Mini because these risk factors may affect the operations and financial results of the Combined Company. These risk factors may be found under Part I, Item 1A, "Risk Factors" in the WillScot 10-K and the Mobile Mini 10-K, as updated by WillScot's and Mobile Mini's respective Quarterly Reports on Form 10-Q or Current Reports on Form 8-K, and future filings with the SEC, each of which is on file or will be filed with the SEC and all of which are or will be incorporated by reference into this joint proxy statement/prospectus. You should also consider the other information in this document and the other documents incorporated by reference into this joint proxy statement/prospectus. See the section entitled "Where You Can Find More Information."

Risks Related to the Merger

The completion of the Merger is subject to a number of conditions, and if these conditions are not satisfied or waived, the Merger will not be completed.

        The obligations of WillScot and Mobile Mini to complete the Merger are subject to satisfaction or waiver of a number of conditions, including: (i) the expiration or termination of the applicable waiting period under the HSR Act without the imposition of a regulatory adverse effect, (ii) approval of the Mobile Mini Merger Proposal by Mobile Mini stockholders at the Mobile Mini special meeting, (iii) approval of the WillScot Stock Issuance Proposal and Combined Company Charter Amendment Proposal by WillScot stockholders at the WillScot special meeting, (iv) approval for the listing on Nasdaq of the Merger Consideration, which will be reclassified as and converted into shares of Combined Company Common Stock at the Effective Time, (v) absence of any law, injunction, judgment, order, decree or other legal restraint or prohibition preventing the consummation of the Merger or any other transaction contemplated by the Merger Agreement and the ancillary agreements and delivery of an officer certificate by the other party certifying satisfaction, (vi) declaration of effectiveness of the Registration Statement on Form S-4, of which this joint proxy statement/prospectus forms a part, (vii) the receipt by each of WillScot and Mobile Mini of an opinion of its respective outside counsel to the effect that the Merger will qualify as a "reorganization" within the meaning of Section 368(a) of the Code, (viii) the debt financing contemplated by the Commitment Letter entered into by WillScot in connection with the Merger having been obtained, (ix) accuracy of the representations and warranties of WillScot or Mobile Mini, as applicable, made in the Merger Agreement by the other party, subject to certain materiality qualifications set forth in the Merger Agreement, (x) performance in all material respects by the other party of the material obligations required to be performed by it at or prior to completion of the Merger, (xi) in the case of Mobile Mini, the completion of the exchange by Sapphire Holding of its shares of WSHC Stock for shares of WillScot Class A Common Stock pursuant to the Voting Agreement, and the concurrent cancellation of all issued and outstanding shares of WillScot Class B Common Stock, (xii) delivery of an officer certificate by each of WillScot and Mobile Mini to the other certifying satisfaction of certain closing conditions and (xiii) the absence of a material adverse effect on the other party (see the section entitled "The Merger Agreement—Representations and Warranties; Material Adverse Effect" beginning on page 164 of this joint proxy statement/prospectus for the definition of material adverse effect). For a more complete summary of the conditions that must be satisfied or waived prior to completion of the Merger, see the section entitled "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 176 of this joint proxy statement/prospectus. There can be no assurance that the conditions to completion of the Merger will be satisfied or waived or that the Merger will be completed.

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The Merger is subject to the expiration or termination of applicable waiting periods and the DOJ or FTC may impose conditions that could have an adverse effect on WillScot, Mobile Mini or the Combined Company or, if not obtained, could prevent completion of the Merger.

        Before the Merger may be completed, any applicable waiting periods (and any extensions thereof) under the HSR Act relating to the completion of the Merger must have expired or been terminated. WillScot and Mobile Mini filed their respective Notification and Report Forms pursuant to the HSR Act, and the waiting period will expire at 11:59 p.m. Eastern Time on May 27, 2020 unless earlier terminated or otherwise extended.

        Under the Merger Agreement, WillScot and Mobile Mini have agreed to use their respective reasonable best efforts to obtain all consents required to be obtained from any governmental authority that are necessary, proper or advisable to consummate the Merger. However, neither WillScot nor Mobile Mini is required to agree to or commit to any actions that individually or in the aggregate would, or could reasonably be expected to have, a material adverse effect on the condition (financial or otherwise), assets, liabilities, business or results of operations of the Combined Company. For a more detailed description of WillScot's and Mobile Mini's obligations to obtain required regulatory authorizations and approvals, see the section entitled "The Merger Agreement—Covenants and Agreements—Efforts to Obtain Regulatory Approval."

        In addition, at any time before or after the completion of the Merger, and notwithstanding the expiration or termination of applicable waiting periods, the DOJ or FTC or any state attorney general could take such action under the antitrust laws as such party deems necessary or desirable in the public interest. Such action could include, among other things, seeking to enjoin the completion of the Merger, to rescind the Merger or to conditionally permit the completion of the Merger subject to regulatory conditions or other remedies. In addition, in some circumstances, a third party could initiate a private action challenging, seeking to enjoin, or seeking to impose conditions on the Merger. WillScot and Mobile Mini may not prevail and may incur significant costs in defending or settling any such action.

        For a more detailed description of the regulatory review process, see the section entitled "The Merger—Regulatory Approvals."

        There can be no assurance that the conditions to the completion of the Merger set forth in the Merger Agreement relating to applicable antitrust laws will be satisfied.

Failure to complete the Merger could negatively impact the stock price and the future business and financial results of WillScot and Mobile Mini.

        If the Merger is not completed for any reason, including as a result of Mobile Mini stockholders failing to approve the Mobile Mini Merger Proposal or WillScot stockholders failing to approve the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal, the ongoing businesses of Mobile Mini and WillScot may be materially and adversely affected and, without realizing any of the benefits of having completed the Merger, Mobile Mini and WillScot would be subject to a number of risks, including the following:

•

WillScot and Mobile Mini may experience negative reactions from the financial markets, including negative impacts on trading prices of WillScot Class A Common Stock, Mobile Mini Common Stock and both companies' other securities, and from their respective customers, suppliers and employees;



•

Mobile Mini may be required to pay WillScot a termination fee of $57,086,000 if the Merger Agreement is terminated under certain circumstances, and WillScot may be required to pay Mobile Mini a termination fee of $66,600,000 if the Merger Agreement is terminated under certain other circumstances. See the sections entitled "The Merger Agreement—Termination"

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and "The Merger Agreement—Expenses and Termination Fees," each beginning on page 178 of this joint proxy statement/prospectus;

•

WillScot and Mobile Mini will be required to pay certain transaction expenses and other costs incurred in connection with the Merger, whether or not the Merger is completed;



•

the Merger Agreement places certain restrictions on the conduct of Mobile Mini's and WillScot's businesses prior to completion of the Merger, and such restrictions, the waiver of which is subject to the consent of the other party, may prevent Mobile Mini and WillScot from making certain acquisitions, taking certain other specified actions or otherwise pursuing business opportunities during the pendency of the Merger that Mobile Mini or WillScot would have made, taken or pursued if these restrictions were not in place (see the section entitled "The Merger Agreement—Covenants and Agreements—Conduct of Business" beginning on page 167 of this joint proxy statement/prospectus for a description of the restrictive covenants applicable to Mobile Mini and WillScot); and



•

matters relating to the Merger (including arranging permanent financing and integration planning) will require substantial commitments of time and resources by WillScot and Mobile Mini management and the expenditure of significant funds in the form of fees and expenses, which would otherwise have been devoted to day-to-day operations and other opportunities that may have been beneficial to either WillScot or Mobile Mini as an independent company.

        There can be no assurance that the risks described above will not materialize. If any of those risks materialize, they may materially and adversely affect WillScot's and/or Mobile Mini's businesses, financial condition, financial results, ratings, stock prices and/or bond prices.

        In addition, WillScot and Mobile Mini could be subject to litigation related to any failure to complete the Merger or related to any proceeding to specifically enforce WillScot's or Mobile Mini's obligation to perform their respective obligations under the Merger Agreement. If the Merger is not completed, these risks may materialize and may materially and adversely affect WillScot's and/or Mobile Mini's businesses, financial condition, financial results, ratings, stock prices and/or bond prices.

The Merger Agreement contains provisions that may make it more difficult for WillScot and Mobile Mini to pursue alternatives to the Merger.

        The Merger Agreement contains provisions that make it more difficult for Mobile Mini to sell its business to a party other than WillScot, or for WillScot to sell its business. These provisions include a general prohibition on each of WillScot and Mobile Mini soliciting any acquisition proposal. Further, there are only limited exceptions to each of WillScot's and Mobile Mini's agreement that its board of directors will not withdraw or modify in a manner adverse to the other the recommendation of its board of directors in favor of the WillScot Proposals or the Mobile Mini Proposals, as applicable, and the other generally has a right to match any acquisition proposal that may be made. However, at any time prior to the approval of the WillScot Proposals or the Mobile Mini Proposals, as applicable, each of WillScot's and Mobile Mini's board of directors is permitted to take certain of these actions if it determines in good faith that the failure to take such action would be inconsistent with its fiduciary duties under applicable law. See the sections entitled "The Merger Agreement—Covenants and Agreements—No Solicitation of Alternative Transactions" and "The Merger Agreement—Covenants and Agreements—Changes in Board Recommendation" beginning on pages 169 and 171, respectively, of this joint proxy statement/prospectus.

        The parties believe these provisions are reasonable and not preclusive of other offers, but these restrictions might discourage a third party that has an interest in acquiring all or a significant part of either Mobile Mini or WillScot from considering or proposing that acquisition, even if that party were prepared to pay consideration with a higher per-share value than the currently proposed Merger Consideration, in the case of Mobile Mini, or that party were prepared to enter into an agreement that

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may be favorable to WillScot or its stockholders, in the case of WillScot. Furthermore, the termination fees described below may result in a potential competing acquirer proposing to pay a lower per-share price to acquire WillScot or Mobile Mini, as applicable, than it might otherwise have proposed to pay because of the added expense of the termination fee that may become payable by such party in certain circumstances.

The Exchange Ratio is fixed and will not be adjusted in the event of any change in either WillScot's or Mobile Mini's stock price.

        The Exchange Ratio of 2.4050 is fixed, which means that it will not change between now and the Effective Time, regardless of whether the market price of either Mobile Mini Common Stock or WillScot Class A Common Stock changes. Upon completion of the Merger, each issued and outstanding share of Mobile Mini Common Stock (other than treasury shares held by Mobile Mini or its subsidiaries) will be converted into the right to 2.4050 shares of WillScot Class A Common Stock (and, if applicable, cash in lieu of fractional shares). Therefore, the value of the Merger Consideration will depend on the market price of the WillScot Class A Common Stock at the Effective Time.

        The market price of the WillScot Class A Common Stock has fluctuated since the date of the announcement of the Merger Agreement and may continue to fluctuate from the date of this joint proxy statement/prospectus to the date of the WillScot special meeting, the Mobile Mini special meeting, the Effective Time and thereafter (at such time it will have been reclassified as and converted into Combined Company Common Stock). The market value of the Merger Consideration to be issued at the Effective Time will not be known at the time of the WillScot special meeting or the Mobile Mini special meeting. Therefore, current and historical market prices of WillScot Class A Common Stock may not reflect the value that Mobile Mini stockholders will receive in the Merger, and the current stock price quotations for Mobile Mini Common Stock and WillScot Class A Common Stock may not provide meaningful information to WillScot stockholders in determining whether to approve the WillScot Proposals or to Mobile Mini stockholders in determining whether to approve the Mobile Mini Proposals. Both WillScot Class A Common Stock and Mobile Mini Common Stock are traded on Nasdaq under the symbols "WSC" and "MINI," respectively.

        We cannot assure you that, following the Merger, the market prices of Combined Company Common Stock will equal or exceed what the combined market price of WillScot Class A Common Stock and Mobile Mini Common Stock would have been in the absence of the Merger. It is possible that after the Merger, the combined equity value of the Combined Company will be less than the combined equity value of WillScot and Mobile Mini before the Merger. WillScot stockholders and Mobile Mini stockholders are encouraged to review carefully the other information contained or incorporated by reference in this joint proxy statement/prospectus. See the section entitled "Where You Can Find More Information."

WillScot's and Mobile Mini's business relationships may be subject to disruption due to uncertainty associated with the Merger.

        Parties with which WillScot or Mobile Mini does business may experience uncertainty associated with the Merger, including with respect to current or future business relationships with WillScot, Mobile Mini or the Combined Company. WillScot's and Mobile Mini's business relationships may be subject to disruption as customers, vendors and others may attempt to negotiate changes in existing business relationships or consider entering into business relationships with parties other than WillScot, Mobile Mini or the Combined Company. These disruptions could have a material adverse effect on the businesses, financial condition, results of operations or prospects of WillScot, Mobile Mini and/or the Combined Company, including a material adverse effect on the Combined Company's ability to realize the anticipated benefits of the Merger. The risk and adverse effect of such disruptions could be exacerbated by a delay in completion of the Merger or termination of the Merger Agreement.

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Uncertainties associated with the Merger may cause a loss of management personnel and other key employees, which could adversely affect the future business and operations of the Combined Company following the Effective Time.

        WillScot and Mobile Mini are dependent on the experience and industry knowledge of their officers and other key employees to execute their business plans. The Combined Company's success after the completion of the Merger will depend in part upon the ability of the Combined Company to retain certain key management personnel and employees of WillScot and Mobile Mini. Prior to the Effective Time, current and prospective employees of WillScot and Mobile Mini may experience uncertainty about their roles following the Merger, which may have an adverse effect on the ability of each of WillScot and Mobile Mini to attract or retain key management and other key personnel. In addition, no assurance can be given that the Combined Company, after the completion of the Merger, will be able to attract or retain key management personnel and other key employees to the same extent that WillScot and Mobile Mini have previously been able to attract or retain their own employees.

The unaudited pro forma condensed combined financial information and prospective financial information included in this joint proxy statement/prospectus is presented for illustrative purposes only and does not represent the actual financial position or results of operations of the Combined Company following completion of the Merger.

        The unaudited pro forma condensed combined financial information and prospective financial information contained in this joint proxy statement/prospectus is presented for illustrative purposes only, contains a variety of adjustments, assumptions and preliminary estimates and does not represent the actual financial position or results of operations of WillScot and Mobile Mini prior to the Merger or that of the Combined Company following the Merger for several reasons. Among other things, the unaudited pro forma condensed combined financial information does not reflect the projected realization of cost savings following completion of the Merger projected integration costs, restructuring costs or any changes in applicable law. See the sections entitled "Unaudited Pro Forma Condensed Combined Financial Information," "The Merger—Certain Unaudited Prospective Financial Information" and "Comparative Historical and Unaudited Pro Forma Per Share Data" beginning on pages 202, 129 and 26, respectively, of this joint proxy statement/prospectus. The actual financial positions and results of operations of Mobile Mini and WillScot prior to the Merger and that of the Combined Company following the Merger may not be consistent with, or evident from, the unaudited pro forma condensed combined financial information or prospective financial information included in this joint proxy statement/prospectus. In addition, the assumptions used in preparing the unaudited pro forma condensed combined financial information and/or the prospective financial information included in this joint proxy statement/prospectus may not be realized and may be affected by other factors. The underlying assumptions were generally based on information and market factors known to WillScot management and Mobile Mini management as of February 23, 2020 (and, as a result do not include any adjustments for the impact or potential impact of any events that took place thereafter, including, but not limited to, the impact of COVID-19 or disruptions in the oil and gas market). Any significant changes in the market price of shares of WillScot Class A Common Stock may cause a significant change in the purchase price used for WillScot's accounting purposes and the pro forma condensed combined financial information contained in this joint proxy statement/prospectus.

WillScot's and Mobile Mini's executive officers and directors have interests in the Merger that may be different from your interests as a WillScot stockholder or Mobile Mini stockholder.

        When considering the recommendation of the WillScot Board that WillScot stockholders vote in favor of the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal and the recommendation of the Mobile Mini Board that Mobile Mini stockholders vote in favor of the Mobile Mini Merger Proposal, WillScot stockholders and Mobile Mini stockholders should be aware that the executive officers and directors of WillScot and Mobile Mini have interests in the

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Merger that may be different from, or in addition to, the interests of WillScot stockholders or Mobile Mini stockholders, as applicable, generally. The WillScot Board was aware of the interests of WillScot's directors and executive officers, the Mobile Mini Board was aware of the interests of Mobile Mini's directors and executive officers, and each board considered such interests, among other matters, when it approved the Merger Agreement and in making its recommendations to its respective stockholders. Additional interests of the directors and executive officers of WillScot in the Merger include the payment of certain severance and other benefits upon a qualifying termination of employment following the completion of the Merger, the designation of Bradley Soultz, Chief Executive Officer of WillScot, as the Chief Executive Officer of the Combined Company pursuant to the terms of an employment agreement with WillScot that will become effective at the Effective Time, the designation of Timothy Boswell, Chief Financial Officer of WillScot, as the Chief Financial Officer of the Combined Company pursuant to the terms of an employment agreement with WillScot that will become effective at the Effective Time, and that, at the Effective Time, the Combined Company Board will consist of 11 directors, including six WillScot Continuing Directors, two of whom are also TDR Continuing Directors. Additional interests of the directors and executive officers of Mobile Mini include the treatment in the Merger of Mobile Mini equity-based awards held by one director and/or executive officers, as applicable, certain severance payments and other benefits that Mobile Mini executive officers are entitled to receive upon a qualifying termination of employment following the completion of the Merger, the designation of Kelly Williams, President and Chief Executive Officer of Mobile Mini, as the President and Chief Operating Officer of the Combined Company pursuant to the terms of an employment agreement with WillScot that will become effective at the Effective Time, the designation of Christopher Miner, General Counsel of Mobile Mini, as the Senior Vice President, General Counsel and Secretary of the Combined Company pursuant to the terms of an employment agreement with WillScot that will become effective at the Effective Time, that, at the Effective Time, the Combined Company Board will consist of 11 directors, including five Mobile Mini Continuing Directors, and rights to continuing indemnification and directors' and officers' liability insurance for current and former directors and executive officers. See "The Merger—Interests of Certain of WillScot's Directors and Executive Officers in the Merger" and "The Merger—Interests of Mobile Mini's Directors and Executive Officers in the Merger" beginning on pages 139 and 145, respectively, of this joint proxy statement/prospectus for a more detailed description of these interests. As a result of these interests, directors and executive officers might be more likely to support and to vote in favor of the proposals described in this joint proxy statement/prospectus than if they did not have these interests. WillScot stockholders and Mobile Mini stockholders should consider whether their interests might have influenced directors and executive officers to recommend adopting the Merger Agreement.

The opinions of the respective financial advisors of the WillScot Board, the WillScot Special Committee and the Mobile Mini Board do not reflect changes in circumstances that may have occurred or that may occur between the signing of the Merger Agreement and the Effective Time.

        None of the WillScot Board, the WillScot Special Committee or the Mobile Mini Board has obtained updated opinions from their respective financial advisors as of the date of this joint proxy statement/prospectus, nor do any of them expect to receive updated, revised or reaffirmed opinions prior to the Effective Time. Changes in the operations and prospects of WillScot or Mobile Mini, general market and economic conditions and other factors that may be beyond the control of WillScot or Mobile Mini, and on which such financial advisors' opinions were based, may significantly alter the value of WillScot, Mobile Mini, the share price of WillScot Class A Common Stock by the Effective Time, or the anticipated benefits of the Merger. The opinions were made solely as of their respective dates and do not speak as of any other date, including the date of this joint proxy statement/prospectus or the date on which the Merger will be completed. Because such financial advisors will not be updating their opinions, the opinions will not address the fairness of the Merger Consideration from a financial point of view at the Effective Time. The WillScot Board's recommendation that WillScot stockholders approve the WillScot Proposals and the Mobile Mini Board's recommendation that Mobile

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Mini stockholders approve the Mobile Mini Proposals, however, were made as of the date of the Merger Agreement and are also made as of the date of this joint proxy statement/prospectus. For a description of the opinions that the WillScot Board, the WillScot Special Committee and the Mobile Mini Board received from their respective financial advisors, see the sections entitled "The Merger—Opinions of WillScot's Financial Advisors" and "The Merger—Opinions of Mobile Mini's Financial Advisors."

Following the Merger, the composition of the Combined Company Board will be different from the composition of the current WillScot Board or the current Mobile Mini Board.

        The WillScot Board currently consists of seven directors and the Mobile Mini Board currently consists of 11 directors. Upon completion of the Merger, the Combined Company Board will consist of 11 directors, including six WillScot Continuing Directors (two of whom are TDR Continuing Directors) and five Mobile Mini Continuing Directors. See the section entitled "The Merger—Governance of the Combined Company" beginning on page 152 of this joint proxy statement/prospectus. This new composition of the Combined Company Board may affect the future decisions of the Combined Company.

Litigation relating to the Merger that has been filed or may be filed against the WillScot Board, the WillScot Special Committee and/or the Mobile Mini Board that could prevent or delay the closing and/or result in the payment of damages following the closing.

        As of April 30, 2020, three complaints have been filed by purported Mobile Mini stockholders challenging the Merger. The complaints generally assert claims under Sections 14(a) and 20(a) of the Exchange Act challenging the adequacy of certain disclosures made in the joint proxy statement/prospectus which forms part of the registration statement on Form S-4 filed with the SEC on April 17, 2020. The complaints seek, among other relief, an injunction preventing Mobile Mini from consummating the transaction, damages in the event that the Merger is consummated, and attorneys' fees. For a more detailed description of litigation in connection with the Merger, see the section entitled "The Merger—Litigation Relating to the Merger."

        The outcome of these lawsuits or any other lawsuit that may be filed challenging the Merger is uncertain and any of these lawsuits and potential other lawsuits could prevent or delay the closing and/or result in substantial costs to WillScot and/or Mobile Mini. Any such actions may create uncertainty relating to the Merger and may be costly and distracting to management. Further, the defense or settlement of any lawsuit or claim that remains unresolved at the Effective Time may adversely affect the Combined Company's business, financial condition, results of operations and cash flows.

If the Merger fails to qualify as a tax-free reorganization for U.S. federal income tax purposes, U.S. holders of shares of Mobile Mini Common Stock may recognize gain or loss for U.S. federal income tax purposes as a result of the Merger.

        The obligations of WillScot and Mobile Mini to complete the Merger are conditioned upon the receipt by each of WillScot and Mobile Mini of an opinion of its respective outside counsel to the effect that the Merger will qualify as a "reorganization" within the meaning of Section 368(a) of the Code. If the Merger qualifies as a "reorganization," U.S. holders of shares of Mobile Mini Common Stock generally will not recognize any gain or loss for U.S. federal income tax purposes upon the receipt of WillScot Class A Common Stock in exchange for Mobile Mini Common Stock in the Merger (other than gain or loss, if any, with respect to any cash received in lieu of a fractional share of WillScot Class A Common Stock). The qualification of the Merger as a "reorganization" depends on numerous facts and circumstances, some of which are not known as of the date of this joint proxy statement/prospectus, and are outside of the parties' control. In addition, opinions of counsel are not

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binding on the IRS or any court, and the IRS or a court may disagree with the conclusions in such opinions of counsel. If the Merger did not qualify as a "reorganization," U.S. holders of shares of Mobile Mini Common Stock generally would recognize gain or loss for U.S. federal income tax purposes on the receipt of WillScot Class A Common Stock in exchange for Mobile Mini Common Stock in the Merger. See the section entitled "The Merger—Material U.S. Federal Income Tax Consequences of the Merger" below for a more detailed discussion of the U.S. federal income tax consequences of the Merger to U.S. holders of shares of Mobile Mini Common Stock if the Merger does not qualify as a "reorganization."

In the event volatile securities markets cause a decrease in the value of the shares of WillScot Class A Common Stock pledged by Sapphire Holding under its margin loan arrangement, such decrease would permit the lenders thereunder to foreclose on any such shares of WillScot Class A Common Stock. Any such foreclosure will result in such shares of WillScot Class A Common Stock no longer being subject to the Voting Agreement.

        The Voting Agreement provides, among other things, that Sapphire Holding will vote all of its shares of WillScot Common Stock in favor of the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal, subject to certain conditions. As previously disclosed, in August 2018, Sapphire Holding pledged all of its shares of WillScot Class A Common Stock as security for a margin loan (the "TDR Margin Loan"), under which Sapphire Holding borrowed $125.0 million dollars. As of March 16, 2020, Sapphire Holding owned approximately 49 million shares of WillScot Class A Common Stock, or 45% of the total issued and outstanding shares of WillScot Class A Common Stock, as of such date, all of which are currently pledged under the terms of the TDR Margin Loan. Any foreclosure under the TDR Margin Loan will result in such shares of WillScot Class A Common Stock no longer being subject to the Voting Agreement. The shares of WillScot Class A Common Stock held by Sapphire Holding constitute a substantial portion of the shares of WillScot Common Stock subject to the Voting Agreement. If such shares of WillScot Class A Common Stock cease to be subject to the Voting Agreement, this could increase uncertainty with respect to receiving the requisite approvals of WillScot stockholders in respect of the Merger, including the WillScot Stock Issuance Proposal and the Combined Company Charter Amendment Proposal. See "Risk Factors—Risks Relating to Our Capital Structure—Our principal stockholder controls a significant amount of our common stock and has substantial control over our business, and it may take actions or have interests that are adverse to or conflict with those of our other stockholders," in the WillScot 10-K for additional information.

Risks Related to the Combined Company

After the completion of the Merger, the Combined Company may fail to realize the anticipated benefits and cost savings of the Merger, which could adversely affect the value of the shares of Combined Company Common Stock.

        The success of the Merger will depend, in part, on the Combined Company's ability to realize the anticipated benefits, including synergies, cost savings and operational efficiencies from combining the businesses of WillScot and Mobile Mini. The Combined Company's ability to realize these anticipated benefits and cost savings is subject to certain risks, including:

•

the Combined Company's ability to successfully integrate the businesses of WillScot and Mobile Mini and control the costs relating thereto;



•

whether the combined businesses will perform as expected;



•

the possibility that the Exchange Ratio does not accurately reflect the value the Combined Company will derive from the acquisition; and



•

the assumption of known and unknown liabilities of WillScot and Mobile Mini.

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        If the Combined Company is not able to successfully integrate the business of Mobile Mini within the anticipated time frame, or at all, or the costs of such combination exceed the current expectation, the anticipated cost savings and other benefits of the Merger may not be realized fully or may take longer to realize than expected, the Combined Company may not perform as expected and the value of the shares of Combined Company Common Stock may be adversely affected.

        WillScot and Mobile Mini have operated and, until completion of the Merger will continue to operate, independently, and there can be no assurances that their businesses can be integrated successfully. It is possible that the integration process could result in the loss of key WillScot or Mobile Mini employees, the disruption of either company's or both companies' ongoing businesses or in unexpected integration issues, higher than expected integration costs and an overall post-completion integration process that takes longer than originally anticipated. Specifically, issues that must be addressed in integrating the operations of WillScot and Mobile Mini in order to realize the anticipated benefits of the Merger so the Combined Company performs as expected include, among other things:

•

combining the companies' separate operational, financial, reporting and corporate functions;



•

integrating the companies' products and services;



•

identifying and eliminating redundant and underperforming operations and assets;



•

harmonizing the companies' operating practices, employee development, compensation and benefit programs, internal controls and other policies, procedures and processes;



•

addressing possible differences in business backgrounds, corporate cultures and management philosophies;



•

consolidating the companies' corporate, administrative and information technology infrastructure;



•

coordinating sales, distribution and marketing efforts;



•

managing the movement of certain businesses and positions to different locations;



•

maintaining existing agreements with customers and suppliers and avoiding delays in entering into new agreements with prospective customers and suppliers;



•

coordinating geographically dispersed organizations;



•

consolidating offices of WillScot and Mobile Mini that are currently in or near the same location; and



•

effecting potential actions that may be required in connection with obtaining regulatory approvals.

        Some of these factors will be outside of WillScot's and/or Mobile Mini's control, and any one of them could result in delays, increased costs, decreases in the amount of expected revenues and other adverse impacts which could materially affect the Combined Company's financial position, results of operations and cash flows.

        In addition, at times, the attention of certain members of each company's management and each company's resources may be focused on completion of the Merger and the integration of the businesses of the two companies and diverted from day-to-day business operations, which may disrupt each company's ongoing business and the business of the Combined Company.

Upon the completion of the Merger, Mobile Mini stockholders and WillScot stockholders will have different rights under the Combined Company's governing documents than they currently have under Mobile Mini's and WillScot's governing documents, respectively.

        Upon the completion of the Merger, Mobile Mini stockholders will no longer be stockholders of Mobile Mini, but will instead become stockholders of the Combined Company and their rights as

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stockholders will be governed by the terms of the A&R Charter and the A&R Bylaws. The terms of the A&R Charter and the A&R Bylaws will be in some respects different than the terms of Mobile Mini's certificate of incorporation and bylaws, which currently govern the rights of Mobile Mini stockholders. Because the certificate of incorporation and bylaws of WillScot are being amended and restated in connection with the Merger, the rights of WillScot stockholders will also change, as the terms of the A&R Charter and the A&R Bylaws will be in some respects different than the terms of WillScot's certificate of incorporation and bylaws, which currently govern the rights of WillScot stockholders. For a more complete description of the different rights associated with shares of Mobile Mini Common Stock and shares of Combined Company Common Stock, see the section entitled "Comparison of the Rights of Stockholders."

Current WillScot stockholders and Mobile Mini stockholders will have a reduced ownership and voting interest after the Merger and will exercise less influence over the management of the Combined Company.

        Upon completion of the Merger, WillScot expects to issue approximately 106.7 million shares of WillScot Class A Common Stock to Mobile Mini stockholders in connection with the transactions contemplated by the Merger Agreement, and immediately thereafter such shares of WillScot Class A Common Stock will become shares of Combined Company Common Stock upon the filing of the certificate of merger. As a result, it is expected that, immediately after completion of the Merger, former Mobile Mini stockholders will own approximately 46% of the outstanding shares of Combined Company Common Stock, and pre-Merger WillScot stockholders will own approximately 54% of the outstanding shares of Combined Company Common Stock. Consequently, current WillScot stockholders and Mobile Mini stockholders in the aggregate will have less influence over the management and policies of the Combined Company than they currently have over the management and policies of WillScot and Mobile Mini, respectively.

The TDR Parties control a significant number of shares of WillScot Common Stock and, following the Merger, will continue to control a significant number of shares of Combined Company Common Stock, providing such parties with substantial influence over the Combined Company's business.

        Upon completion of the Merger, the TDR Parties are expected to beneficially own approximately 26% of the issued and outstanding shares of Combined Company Common Stock and two directors nominated by the TDR Parties will serve on the Combined Company Board. As a result, the TDR Parties may have substantial influence over matters requiring approval by the Combined Company stockholders, including the election and removal of directors, amendments to the A&R Charter and the A&R Bylaws, any proposed merger, consolidation or sale of all or substantially all of the Combined Company's assets and other corporate transactions. The TDR Parties may have interests that are different from those of other stockholders.

        The TDR Parties' ownership of the shares of Combined Company Common Stock may adversely affect the trading price for the Combined Company Common Stock to the extent investors perceive disadvantages in owning shares of a company with a significant stockholder or in the event Sapphire Holding's takes any action with its shares that could result in an adverse impact on the price of the Combined Company Common Stock, including a sale of any portion of their shares of the Combined Company Common Stock.

The future results of the Combined Company may be adversely impacted if the Combined Company does not effectively manage its expanded operations following completion of the Merger.

        Following completion of the Merger, the size of the Combined Company's business will be significantly larger than the current size of either WillScot's or Mobile Mini's respective businesses. The Combined Company's ability to successfully manage this expanded business will depend, in part, upon management's ability to implement an effective integration of the two companies and its ability to

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manage a combined business with significantly larger size and scope with the associated increased costs and complexity. There can be no assurances that the management of the Combined Company will be successful or that the Combined Company will realize the expected operating efficiencies, cost savings and other benefits currently anticipated from the Merger.

Each of WillScot and Mobile Mini expects to incur substantial expenses related to the completion of the Merger and the integration of the businesses of WillScot and Mobile Mini.