Y-mAbs Therapeutics (YMAB) SC 13GY-mAbs Therapeutics / WG Biotech ApS ownership change

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. )*

Y-mAbs Therapeutics, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value per share

(Title of Class of Securities)

984241109

(CUSIP Number)

December 31, 2019

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Explanatory Note

This Schedule 13G discloses securities beneficially owned by certain Reporting Persons (defined below) as of December 31, 2022 and includes disclosures for which a Schedule 13G and Amendment No. 1 thereto were previously inadvertently not filed by the Reporting Persons as of the years ended December 31, 2019 and 2021, respectively.

Y-mAbs Therapeutics, Inc., a Delaware corporation (the “Issuer”)

230 Park Avenue, Suite 3350

New York, New York 10169

This statement is filed by the following reporting persons (collectively referred to as the “Reporting Persons”):

WG Biotech ApS

Johan Wedell-Wedellsborg

The address of the principal business office of the Reporting Persons is c/o WG Biotech ApS, Rungsted Strandvej 113, Rungsted Kyst, G7, 2960.

The citizenship of each of the Reporting Persons is Denmark.

Common Stock, $0.0001 par value per share (“Common Stock”)

984241109

This statement is not filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c).

The information contained in Rows 5 through 9 and 11 on each of the cover pages of this Schedule 13G is incorporated by reference in its entirety into this Item 4.

(a)           Amount beneficially owned:

As of December 31, 2022, WG Biotech ApS directly held 4,178,465 shares of Common Stock, representing approximately 9.6% of the outstanding shares of Common Stock. This percentage of beneficial ownership is based on 43,669,509 shares of Common Stock of the Issuer outstanding as of December 31, 2022, as provided by the Issuer.

As of December 31, 2022, Mr. Wedell-Wedellsborg directly held 126,666 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2022. In addition, Mr. Wedell-Wedellsborg may be deemed to beneficially own the 4,178,465 shares of Common Stock directly owned by WG Biotech ApS, of which entity Mr. Wedell-Wedellsborg is the majority owner. The aggregate of 4,305,131 shares of Common Stock with respect to which Mr. Wedell-Wedellsborg may be deemed to beneficially own represents approximately 9.8% of the outstanding shares of Common Stock. This percentage of beneficial ownership is based on dividing (a) the aggregate 4,305,131 shares of Common Stock that Mr. Wedell-Wedellsborg may be deemed to beneficially own as of December 31, 2022, by (b) the sum of (i) 43,669,509 shares of Common Stock outstanding as of December 31, 2022, as provided by the Issuer, and (ii) 126,666 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2022 which are deemed outstanding for purposes of this calculation. Mr. Wedell-Wedellsborg disclaims beneficial ownership over the shares held by WG Biotech ApS for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Act”), and this Schedule 13G shall not be deemed an admission that Mr. Wedell-Wedellsborg is the beneficial owner of such shares for Section 13(d) of the Act or any other purpose.

(b)           Percent of Class:

See responses to Item 11 on each cover page and Item 4(a) above.

(c)           Number of shares as to which the Reporting Person has:

(i)            Sole power to vote or to direct the vote:

See response to Item 5 on each cover page.

(ii)          Shared power to vote or to direct the vote:

See response to Item 6 on each cover page.

(iii)         Sole power to dispose or to direct the disposition of:

See response to Item 7 on each cover page.

(iv)          Shared power to dispose or to direct the disposition of:

See response to Item 8 on each cover page.

A Schedule 13G and Amendment No. 1 thereto were previously inadvertently not filed pursuant to Rule 13d-1(d) under the Act by the Reporting Persons as of the years ended December 31, 2019 and 2021, respectively, as described below.

The Reporting Persons inadvertently failed to file an initial Schedule 13G as of the year ended December 31, 2019. As of December 31, 2019, WG Biotech ApS directly held 5,508,392 shares of Common Stock, representing approximately 13.9% of the outstanding shares of Common Stock on such date. As of December 31, 2019, Mr. Wedell-Wedellsborg directly held 68,444 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2019, and Mr. Wedell-Wedellsborg may have been deemed to beneficially own the 5,508,392 shares of Common Stock directly held by WG Biotech ApS, of which entity Mr. Wedell-Wedellsborg was the majority owner at such time. The aggregate of 5,576,836 shares of Common Stock with respect to which Mr. Wedell-Wedellsborg may have been deemed to beneficially own represented approximately 14.0% of the outstanding shares of Common Stock as of December 31, 2019. This percentage of beneficial ownership is based on dividing (a) the aggregate 5,576,836 shares of Common Stock that Mr. Wedell-Wedellsborg may be deemed to beneficially own as of December 31, 2022, by (b) the sum of (i) 39,728,416 shares of Common Stock outstanding as of December 31, 2019, and (ii) 68,444 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2019 which are deemed outstanding for purposes of this calculation.

The Reporting Persons also inadvertently failed to file an Amendment No. 1 to Schedule 13G as of the year ended December 31, 2021. As of December 31, 2021, WG Biotech ApS directly held 4,178,465 shares of Common Stock, representing approximately 9.6% of the outstanding shares of Common Stock on such date. As of December 31, 2021, Mr. Wedell-Wedellsborg directly held 92,888 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2021, and Mr. Wedell-Wedellsborg may have been deemed to beneficially own the 4,178,465 shares of Common Stock directly held by WG Biotech ApS, of which entity Mr. Wedell-Wedellsborg was the majority owner at such time. The aggregate of 4,271,353 shares of Common Stock with respect to which Mr. Wedell-Wedellsborg may have been deemed to beneficially own represented approximately 9.8% of the outstanding shares of Common Stock as of December 31, 2021. This percentage of beneficial ownership is based on dividing (a) the aggregate 4,271,353 shares of Common Stock that Mr. Wedell-Wedellsborg may be deemed to beneficially own as of December 31, 2022, by (b) sum of (i) 43,694,716 shares of Common Stock outstanding as of December 31, 2021, and (ii) 92,888 shares of Common Stock issuable to Mr. Wedell-Wedellsborg upon exercise of stock options exercisable within 60 days after December 31, 2021 which are deemed outstanding for purposes of this calculation.

Not applicable.

Not applicable.

Not applicable.

Not applicable.

Not applicable.

Not applicable.

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: February 14, 2023

EXHIBIT INDEX

Exhibit No.

1           Joint Filing Agreement, dated as of February 14, 2023