One Stop Systems (OSS) 424B5Prospectus supplement for primary offering

Filed pursuant to Rule 424(b)(5)
Registration Statement No. 333-231513

PROSPECTUS SUPPLEMENT (To Prospectus Dated June 19, 2019)

1,497,006 Shares of Common Stock

We are offering an aggregate of 1,497,006 of our common shares pursuant to a Securities Purchase Agreement, dated March 1, 2021, between us and the purchaser identified therein (the “Purchaser”) pursuant to this prospectus supplement and the accompanying prospectus. The per share offering price of the shares is $6.68.

Our common shares are traded on the Nasdaq Capital Market under the symbol “OSS.” On March 1, 2021, the last reported sale price of our common shares as reported on the Nasdaq Capital Market was $8.87 per share.

The net proceeds to the Company of approximately $9.3 million, after deducting certain fees and expenses associated with the transaction, are to be used for working capital and general corporate purposes.

Investing in our common stock involves risks, including that the trading price of our common stock has been subject to volatility and investors in this offering may not be able to sell their shares of common stock above the actual offering price or at all. You should carefully read and consider the “Risk Factors” beginning on page S-8 of this prospectus before investing. You should also consider the risk factors described or referred to in any documents incorporated by reference in this prospectus supplement and the accompanying prospectus before investing in these securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

We have retained A.G.P./Alliance Global Partners as the lead placement agent and The Benchmark Company, LLC, as co-placement agent (the “Placement Agents”). The Placement Agents have agreed to use their reasonable best efforts to sell the securities offered by this prospectus supplement and the accompanying prospectus. The Placement Agents are not purchasing or selling any shares offered by this prospectus supplement and the accompanying prospectus. See “Plan of Distribution” beginning on page S-12 of this prospectus supplement for more information regarding these arrangements.

Delivery of the shares offered hereby is expected to be made on or about March 3, 2021.

Lead Placement Agent

A.G.P.

Co-Placement Agent

The Benchmark Company, LLC

The date of this prospectus supplement is March 1, 2021.

TABLE OF CONTENTS

Prospectus Supplement

Prospectus

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ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying prospectus are part of a registration statement on Form S-3 (File No. 333-231513) that we filed with the Securities and Exchange Commission (the “SEC”) and that was declared effective by the SEC on June 19, 2019. Under this shelf registration process, we may, from time to time, offer common stock, preferred stock, debt securities, warrants, subscription rights and units, of which this offering is a part.

This document is in two parts. The first part is this prospectus supplement, which describes the terms of this offering of common stock and also adds, updates and changes information contained in the accompanying prospectus and the documents incorporated herein by reference. The second part is the accompanying prospectus, which provides more general information about our common stock and other securities that do not pertain to this offering. To the extent that the information contained in this prospectus supplement conflicts with any information in the accompanying prospectus or any document incorporated by reference, the information in this prospectus supplement shall control. The information in this prospectus supplement may not contain all of the information that is important to you. You should read this entire prospectus supplement, the accompanying prospectus and the documents incorporated by reference carefully before deciding whether to invest in our securities.

References to “our company,” “we,” “our” and “us” in this prospectus supplement and the accompanying prospectus are to One Stop Systems, Inc. and its consolidated subsidiaries, unless the context otherwise requires. This document may include trade names and trademarks of other companies. All such trade names and trademarks appearing in this document are the property of their respective holders.

DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, each prospectus supplement and the information incorporated by reference in this prospectus and each prospectus supplement contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, which we refer to as the Securities Act, and Section 21E of the Exchange Act of 1934, as amended, which we refer to as the Exchange Act, that involve a number of risks and uncertainties. Although our forward-looking statements reflect the good faith judgment of our management, these statements can only be based on facts and factors currently known by us. Consequently, these forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from results and outcomes discussed in the forward-looking statements.

Forward-looking statements can be identified by the use of forward-looking words such as “believes,” “expects,” “hopes,” “may,” “will,” “plan,” “intends,” “estimates,” “could,” “should,” “would,” “continue,” “seeks,” “pro forma,” or “anticipates,” or other similar words (including their use in the negative), or by discussions of future matters. These statements include but are not limited to statements under the captions “Business,” “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and in other sections included in any applicable prospectus supplement or incorporated by reference from our Annual Report on Form 10-K and Quarterly Reports on Form 10-Q, as applicable, as well as our other filings with the SEC. You should be aware that the occurrence of any of the events discussed under the heading “Risk Factors” in any applicable prospectus supplement and any documents incorporated by reference herein or therein could substantially harm our business, operating results and financial condition and that if any of these events occurs, it could adversely affect the value of an investment in our securities.

The cautionary statements made in this prospectus are intended to be applicable to all related forward-looking statements wherever they may appear in this prospectus or in any prospectus supplement or any documents incorporated by reference herein or therein. We urge you not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. Except as required by law, we assume no obligation to update our forward-looking statements, even if new information becomes available in the future.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary description about us and our business highlights selected information contained elsewhere in, or incorporated by reference into, this prospectus supplement and the accompanying prospectus. It does not contain all the information you should consider before investing in our common stock. Before making an investment decision, you should read carefully this prospectus supplement and the accompanying prospectus, including, without limitation, the “Risk Factors” beginning on page S-8 of this prospectus supplement, and any other offering materials, together with the additional information described under the captions “Where You Can Find More Information” and “Information Incorporated by Reference,” beginning on page S-15 of this prospectus supplement.

Our Company

One Stop Systems (OSS) designs, manufactures and markets specialized high-performance computing modules and systems targeting edge deployments. These specialized computers incorporate state-of-the art components and allow our customers to offer high-end computing capabilities (often embed within their equipment) to their target markets. Edge computing is when data is processed/analyzed on devices, that is, at the edge of the network, rather than in the cloud itself. Factors such as increase in load on the cloud infrastructure globally and rise in number of intelligent applications are the major factors driving the growth of the edge computing market. Our customer applications often require connection to a wide array of data sources and sensors, ultra-fast processing power and the ability to quickly access and store large and ever-growing data sets at their location not in the cloud. This equipment requires datacenter class performance optimized for deployment at the edge. We are uniquely positioned as a specialized provider for the high-end of this marketplace providing custom servers, data acquisition platforms, compute accelerators, solid-state storage arrays, system IO expansion systems as well as edge optimized industrial and panel PCs, tablets and handheld compute-devices. We deliver this high-end technology to our customers through the sale of equipment and embedded software.

Through our AI on the Fly ^® initiative, we are delivering innovative specialized high-performance edge computing building blocks and platforms used by our customers to develop products for scientists, engineers, creators and other professionals. These professional mission critical applications capture and store data and quickly, securely, and cost effectively transform it into actionable intelligence at the edge.

High-performance computing applications are moving beyond the traditional academic and scientific realms to broad application across the spectrum of vertical markets. These applications include computationally intense areas like artificial intelligence (AI), deep learning, media and entertainment, test and measurement, medical imaging, genomics, cyber security, automotive, aerospace and defense. We are well positioned to leverage these market trends and capitalize on our unique core competencies in high speed system design and edge system optimization. We have a proven track record of delivering first-to-market advanced technologies and have continued to do so with next generation PCI Express (PCIe) based input/output expansion systems, compute acceleration systems and high-performance flash array storage systems. PCIe offers the highest performance and lowest latency which is critical for our target applications. Edge optimizations include rugged chassis design with light-weight removable high-capacity canisters. These products fit solidly into the emerging markets for specialized high-performance computing at the edge.

The more data input, GPU compute acceleration and flash-based storage resources available to a server, the faster it can acquire, process, store, and retrieve data. In cases where the amount of these resources does not fit within the constraints of a conventional server, PCIe is used to disaggregate the resources into a multi-chassis solution. We have built leading edge expertise in PCIe expansion technology and leverage it to design and build systems that offer a high quantity and density of GPU compute acceleration, flash storage and data I/O interfaces.

A key element of our product strategy is technological leadership. We believe a first-to-market strategy is key to our ability to continue to win significant OEM design wins. As a result, we continue to develop new state-of-the-art products providing first to market next-generation PCIe based building blocks and systems. Our

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ability to drive the leading edge of technology is enabled by our strong relationships with strategic component manufactures, including NVIDIA (for GPUs), Western Digital and Micron (for flash memory); Broadcom (for PCIe switch components), Mellanox (for networking) and Intel, AMD and Marvel (for CPUs). In each of these cases, OSS has access to product roadmaps and other technical information relating to future technology. Access to this information allows us to begin our design process well before the future components we are designing for even exist. This accelerates our time-to-market and allows us to produce and release state-of-the-art designs well ahead of our competitors.

OSS sells its products worldwide to industry leading customers. We service over 1,800 customers per year worldwide, with major repeat customers including disguise, National Instruments, Raytheon, Thales, and Alcon. We anticipate continued market growth in our target markets and sustaining the ability to increase market share through our leading technology, engineering expertise, supply chain management and go-to-market innovation.

Industry Background

High performance computing refers to computing solutions capable of ingesting and processing large amounts of data and storing and retrieving that data at speeds 10-1,000 times faster than a typical corporate computer. Increasingly, commercial companies, financial entities, governmental agencies, including the Department of Defense and academic institutions are turning to high-performance computing solutions to analyze vast amounts of data to obtain meaningful and actionable insights. Three technologies are fundamental: GPU compute accelerators, flash memory based storage, and high speed data acquisition I/O. These technologies enable systems to ingest, process and store data at significantly higher rates than traditional systems. By harnessing large quantities of these components, companies can receive necessary data analyses much more quickly, turning raw data to actionable intelligence. Industry experts typically divide the high-performance computing market into the following categories:

The markets for these products are large and growing. The industry sectors that are currently or anticipated to require high-performance computing systems include:

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These industry sectors expect to deploy increasingly faster computing systems to meet industry and competitive goals. GPU computer acceleration, high-performance flash storage and data acquisition are key subsets of the high-performance computing market.

Core Technical Capabilities

OSS has developed unique expertise and core competency across the fundamental technologies of today’s rapidly expanding specialized high-performance computing marketplace. These valuable assets are embedded in the leading-edge engineering capabilities of our engineers, the proprietary intellectual property residing in our vast library of designs, and our brand equity based on our reputation as a high-quality producer of state-of-the-art custom and standard solutions across a broad array of markets.

High Speed System Interconnect Design

Our electrical engineers are experts in high speed digital signaling design. They have continually designed at the leading edge of the state-of-the-art signaling speeds, as semiconductor technology has driven up the clock rate of digital transmission. We have consistently been among a small handful of companies able to come to market first with the latest technology. In fact, we delivered the industry’s first PCIe over cable solutions for PCIe Gen 1, Gen 2, Gen 3 and Gen 4 and are currently on track to accomplish this again in Gen 5. The expertise required includes circuit design, PCB (printed circuit board) layout and routing optimizations all with a focus on achieving the highest levels of signal integrity. In our current systems, PCIe Gen 4 signals are propagated across multiple PCBs, connectors, and copper cabling while maintaining the ability to recognize digital signal transitions at 16 billion times per second.

In high-performance computing systems, especially on the edge, the trajectory of ever increasing signaling speeds is continuing. An ever-shrinking set of companies have the capability to design robust, highly-reliable systems at these speeds. We believe our core competency in large-scale, high-speed design and layout will allow us to remain on the forefront of this growing industry.

Complex System Design

In addition to low-level signal integrity design expertise, we have amassed expertise and intellectual property in high-performance system architecture design. This expertise allows us to develop extremely sophisticated systems with massive scaling, while meeting customer demands for reliability, cost, and flexibility.

We have developed the deep knowledge for high-capacity input/output systems and operating system adjustments and configuration tuning required. Our engineers are often called upon to co-design with OEM designers to create the perfect fit solution for their customers.

For highly scalable systems, a deep understanding and experience with switching topologies and interconnect fabric design is required. We have worked with serial switching technology starting with the first generation of PCIe and have been an innovator in creating unique and flexible topologies to meet the specific needs of the customers. Creating custom solutions for unique customer solutions is a core competency and relies on this deep knowledge of switch capabilities and limitations.

For maximum system performance, design for optimizing data transfer speeds is also an important consideration. OSS has developed expertise in system design to leverage peer-to-peer data flows between GPUs and pioneering techniques for optimized data flows between flash storage and GPU compute engines. Our systems optimize

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switch and GPU configuration topologies to optimize GPU-to-GPU communication without requiring latency-inducing data transfer between host dual processors. Our platforms feature RDMA (remote direct memory access) across compute nodes, which support data transfer without burdening the host CPU.

OSS has pioneered the ability to extend the PCIe bus beyond the confines of a single enclosure, opening the possibility of flexible system expansion options. We believe we are one of the leading designers and suppliers of PCIe host bus adapters that extend PCIe signals from the host motherboard across copper or optical cables to expansion enclosures. OSS adapters provide both ends of the external cable connection. Our expertise in high-speed signal design in printed circuit boards, connectors and cables is essential to successful expansion designs. We also hold expertise in incorporating clustering and rack scale expansion into our system designs, including 100/200 gigabit Ethernet, 100/200 gigabit Infiniband, and emerging PCIe top-of-rack switch technology.

Expertise in power, cooling and mechanical design are required to address the requirements of the high-performance computing customers especially while meeting the constrained time requirements of edge deployments. We have developed leadership design capability in high-power design and distribution within large rack enclosures as well as edge optimized configurations. High-end GPUs today require 350 watts or above, and in our high-end systems up to 16 of these can reside in a single chassis. Thousands of kilowatts of redundant power are required. Power stability and huge thermal loads are some of the critical design issues that must be addressed.

We have expertise in power distribution, redundant power and complex chassis cooling design, including materials selection, airflow simulation, fan technology and cable routing. We have also developed extensive intellectual property in regulatory compliance of complex high-performance computing system design across emission, shock, vibration, thermal, humidity and other environmental requirements that are required for highly reliable and highly available solutions. OSS engineers are experts in design for regulatory testing for FCC (Federal Communications Commission), CE (European Conformity), UL (Underwriters Laboratories), and Mil-Spec (Military Standard) standards. Additionally, we have expertise in rapid prototyping, design for manufacturability, and design for serviceability.

Storage Management Software

Given our hardware design and integration expertise, we see the next natural step is to add a robust software capability that will allow us to offer more optimized and customized systems. Our Ion software design team provides the expertise to deliver full server and storage solutions that produce the highest performance from today’s leading-edge flash storage devices.

The Ion software allows flash-based modules to be put into a variety of storage and network configurations which can then be accessed by multiple servers. The Ion software can do this cost-effectively, while preserving the low latency that is vital for many business and mission-critical enterprise applications, from database and transaction processing to massive data collection programs. Ion also has a full high-availability option to ensure complete data integrity.

In-house mature and established foundational storage software allows OSS to add new products and capabilities to its product portfolio. Possibilities range from increasing data efficiency with snapshot, de-duplication and compression, to improving system manageability and adding NVMe over Fabrics storage scale out capabilities to our products.

Benefits of Technology and Core Capabilities to our Customers

Due to our core capabilities, we can provide our high-performance computing customers with platforms possessing high reliability and cost effectiveness. Such performance allows our customers to solve bigger problems faster, and save the cost and time of highly-paid engineers, data scientists, and other human resources. Our technology enhances innovation by allowing more ‘what-if’ analysis in a finite amount of time. Our price/

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performance leadership enhances our customers’ competitiveness, and lowers capital expense and total cost of ownership. We work with our OEM customers to develop custom ‘perfect fit solutions’ for their unique requirements.

Our Products

OSS has developed a complete line of products that have been customized for the benefit of its customers.

GPU Appliances – high-density, fully integrated computer clusters that are purpose-built for user applications. They provide thousands of cores and hundreds of teraflops of computing performance.

GPU Expansion – expansion units can add hundreds or thousands of computing cores with hundreds of teraflops of computing performance to virtually any OEM server.

Flash Storage and Network Appliances – networked storage appliances optimized for the environment and system software of our customers. These offer flexible and powerful turnkey, customer-driven solutions for the HPC market.

Flash Storage Arrays – arrays that provide hundreds of terabytes of storage and millions of input/output operations per second with flash memory. They are flexible, powerful, and configurable for customers in the HPC market.

Servers – OSS designs servers optimized for PCIe-over-cable expansion. Available in various turn-key and custom configurations, they provide simple, reliable and cost-effective server solutions. These servers are optimized to work seamlessly with other OSS systems and appliances.

Desktop Computing Appliances – OSS designs and builds desktop expansion appliances in many configurations that add input/output flexibility to any user’s desktop system. These appliances come pre-configured with many combinations of flash memory, GPUs, and other add-in boards.

PCIe Expansion – PCIe is the standard for high speed connectivity from a server to a PCIe device. It provides vastly faster throughput compared to USB or Ethernet in a simple, cost-effective connection. It requires no special software, which adds no overhead to the system, and improves latency of throughput. OSS provides cables, kits, backplanes, enclosures, switches, and adaptor cards for this market.

Industrial and Panel PCs – OSS provides small form factor high performance compute platforms customizable to meet needs in industrial applications on the edge where space constraint is a fundamental consideration.

Tablets and Handhelds – OSS provides ruggedized mobile high-performance compute devices that meet the specialized requirement for devices deployed at the edge in a diverse set of environmental conditions.

Corporate Information

Our principal executive offices are located at 2235 Enterprise Street, Suite 110, Escondido, CA 92029 and our telephone number is (760) 745-9883. Our website address is www.onestopsystems.com. Information contained in, or accessible through, our website is not part of this prospectus, and the inclusion of our website address is for reference purposes only.

Where You Can Find More Information

For additional information as to our business, properties and financial condition, please refer to the documents cited in “Where You Can Find More Information.”

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THE OFFERING

The following summary is provided solely for your convenience and is not intended to be complete. You should read the full text and more specific details contained elsewhere in this prospectus supplement and the accompanying prospectus. For a more detailed description of our common stock, see “Description of Capital Stock” in the accompanying prospectus.

The number of shares of our common stock to be outstanding immediately before this offering is based on 16,912,312 shares of common stock outstanding at March 1, 2021, which excludes, as of that date:

Unless otherwise indicated, all information in this prospectus supplement assumes no exercise of the outstanding options or warrants described above, and no vesting of restricted stock units described above.

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RISK FACTORS

An investment in our securities involves a high degree of risk. You should carefully consider the specific risks described in our Annual Report on Form 10-K for the year ended December 31, 2019 under the heading “Risk Factors” and subsequent quarterly reports before investing in our securities. You should also consider similar information in any Annual Report on Form 10-K and Quarterly Report on Form 10-Q or other documents filed by us with the SEC after the date of this prospectus supplement before deciding to invest in our securities. If any of the foregoing risks actually materializes, our business, financial condition, results of operations and prospects could be materially adversely affected. As a result, the value of our securities could decline and you could lose part or all of your investment. The foregoing risks are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also materially affect our business, financial condition, results of operations and prospects. See “Where You Can Find More Information” and “Information Incorporated by Reference,” beginning on page S-15 of this prospectus supplement.

Risks Related to This Offering

Our management has broad discretion as to the use of the net proceeds from this offering.

We cannot specify with certainty the particular uses of the net proceeds we will receive from this offering, and these uses may vary from our current plans. Our management will have discretion in the application of the net proceeds, including for working capital and general corporate purposes as described in “Use of Proceeds.” Accordingly, you will have to rely upon the judgment of our management with respect to the use of the proceeds. Our management may spend a portion or all of the net proceeds from this offering in ways that holders of our common stock may not desire or that may not yield a significant return or any return at all. The failure by our management to apply these funds effectively could harm our business. Pending their use, we may also invest the net proceeds from this offering in a manner that does not produce income or that loses value.

A large number of shares issued in this offering may be sold in the market following this offering, which may depress the market price of our common stock.

A large number of shares issued in this offering may be sold in the market following this offering, which may depress the market price of our common stock. Sales of a substantial number of shares of our common stock in the public market following this offering could cause the market price of our common stock to decline. If there are more shares of common stock offered for sale than buyers are willing to purchase, then the market price of our common stock may decline to a market price at which buyers are willing to purchase the offered shares of common stock and sellers remain willing to sell the shares. All of the shares of common stock issued in the offering will be freely tradable without restriction or further registration under the Securities Act.

The market price for our common stock is particularly volatile given our status as a relatively new public company with a small and thinly traded public float, which could lead to wide fluctuations in our share price.

The market for our common stock is characterized by significant price volatility when compared to the shares of larger, more established companies that have large public floats, and we expect that our share price will continue to be more volatile than the shares of such larger, more established companies for the indefinite future. The volatility in our share price is attributable to a number of factors. First, as noted above, our common stock is, compared to the shares of such larger, more established companies, thinly traded. The price for our shares could, for example, decline precipitously in the event that a large number of our common stock is sold on the market without commensurate demand. Secondly, an investment in our securities is a speculative or “risky” investment due to our lack of significant profits to date. As a consequence of this enhanced risk, more risk-adverse investors may, under the fear of losing all or most of their investment in the event of negative news or lack of progress, be more inclined to sell their shares on the market more quickly and at greater discounts than would be the case with the stock of a larger, more established company that trades on a national securities exchange and has a large

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public float. Many of these factors are beyond our control and may decrease the market price of our common stock regardless of our operating performance.

If you purchase our common stock in this offering, you will incur immediate and substantial dilution in the book value of your shares. You will experience further dilution if we issue additional equity securities in the future.

Investors purchasing shares of common stock in this offering will pay a price per share that substantially exceeds the as adjusted book value per share of our tangible assets after subtracting our liabilities. As a result, investors purchasing shares of common stock in this offering will incur immediate dilution of $5.25 per share, representing the difference between the public offering price of $6.68 per share and our as adjusted net tangible book value as of September 30, 2020.

This dilution is due to the substantially lower price paid by our investors who purchased shares prior to this offering as compared to the price offered to the public in this offering, and the exercise of stock options granted to our employees. In addition, as of September 30, 2020, we had outstanding options and warrants to purchase 1,887,420 shares of our common stock; the exercise of any of these options or warrants would result in additional dilution. As a result of the dilution to investors purchasing shares in this offering, investors may receive significantly less than the purchase price paid in this offering, if anything, in the event of our liquidation.

In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt or other equity linked securities, the issuance of these securities could result in further dilution to our stockholders or result in downward pressure on the price of our common stock.

We do not anticipate paying dividends on our common stock in the foreseeable future; you should not buy our securities if you expect dividends.

The payment of dividends on our common stock will depend on earnings, financial condition and other business and economic factors affecting us at such time as our board of directors may consider relevant. If we do not pay dividends, our common stock may be less valuable because a return on your investment will only occur if our stock price appreciates.

We currently intend to retain our future earnings to support operations and to finance expansion and, therefore, we do not anticipate paying any cash dividends on our common stock in the foreseeable future.

We are a “smaller reporting company” and, as a result of the reduced disclosure and governance requirements applicable to smaller reporting companies, our common stock may be less attractive to investors.

We are a “smaller reporting company,” and we are subject to lesser disclosure obligations in our SEC filings compared to other issuers. Specifically, “smaller reporting companies” are able to provide simplified executive compensation disclosures in their filings, are exempt from the provisions of Section 404(b) of the Sarbanes- Oxley Act requiring that independent registered public accounting firms provide an attestation report on the effectiveness of internal control over financial reporting and have certain other decreased disclosure obligations in their SEC filings, including, among other things, only being required to provide two years of audited financial statements in annual reports. Decreased disclosures in our SEC filings due to our status as a “smaller reporting company” may make it harder for investors to analyze our operating results and financial prospects.

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Risks Related to COVID-19

We must successfully navigate the demand, supply and operational challenges associated with the ongoing coronavirus (COVID-19) pandemic.

Our business has begun to be negatively affected by a range of external factors related to COVID-19 that are not within our control. For example, numerous measures have been implemented by governmental authorities across the globe to contain the virus, including travel bans and restrictions, quarantines, shelter-in-place orders, restrictions and limitations of public gatherings, and business limitations and shutdowns. Many of our customers’ businesses have been severely impacted by these measures and some have been required to reduce employee headcount as a result. If a significant number of our customers are unable to continue as a going concern, this would have an adverse impact on our business and financial condition. In addition, many of our customers are working remotely, which may delay the timing of new business and implementations of our services. If COVID-19 continues to have a substantial impact on our partners, customers, or suppliers, our results of operations and overall financial performance will be harmed.

The impacts of COVID-19 on our business, customers, partners, suppliers, employees, markets and financial results and condition are uncertain, evolving and dependent on numerous unpredictable factors outside of our control, including:

If we are not able to respond to and manage the impact of such events effectively, our business will be harmed.

At present, it is clear the global economy has been negatively impacted by COVID-19, and demand for some of our products and services have been reduced due to uncertainty and the economic impact of COVID-19. For example, customers in certain of the industries most impacted by COVID-19, have requested, and we expect will continue to request, relief to existing contracts or payment obligations, and the impact of those is uncertain. For example, some customers are delaying payments owed to the Company while they address immediate financial crises in their operations due to COVID-19. In particular, in the media and entertainment industry, demand for the use of outdoor media equipment has been impacted due to restrictions on public gatherings. Until such restrictions improve, we expect that demand for certain of our clients’ products and services will be limited, and thus, may impact our financial results and operations.

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More generally, COVID-19 raises the possibility of an extended global economic downturn, which could affect demand for our products and services and impact our results and financial condition even after the pandemic is contained and remediation/restriction measures are lifted. For example, we may be unable to collect receivables from customers that are significantly impacted by COVID-19. Also, a decrease in orders in a given period could negatively affect our revenues in future periods. COVID-19 may also have the effect of heightening many of the other risks described in the “Risk Factors” section of our Annual Report on Form 10-K, including risks associated with our customers and supply chain. We will continue to evaluate the nature and extent of the impact of COVID-19 to our business.

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USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds from the sale of the securities offered hereby. We currently intend to use the net proceeds from the sale of the securities offered hereby for working capital and general corporate purposes. We are restricted from using the proceeds from the sale of the securities for satisfaction of indebtedness of the Company, the redemption or repurchase of any securities of the Company, the settlement of any outstanding litigation, or in violation of FCPA or OFAC regulations.

The principal purposes of this offering are to increase our operating and financial flexibility. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds we will have upon completion of this offering. Accordingly, our management will have broad discretion in the application of net proceeds, if any.

DIVIDEND POLICY

We have never declared or paid any cash dividends on our capital stock, and we do not currently intend to pay any cash dividends on our common stock for the foreseeable future. We expect to retain future earnings, if any, to fund the development and growth of our business. Any future determination to pay dividends on our common stock will be at the discretion of our board of directors and will depend upon, among other factors, our results of operations, financial condition, capital requirements and any contractual restrictions.

DILUTION

Our net tangible book value as of September 30, 2020 was approximately $16,714,640 or approximately $1.01 per share of common stock. Net tangible book value represents total tangible assets less total liabilities. Net tangible book value per share represents net tangible book value divided by the total number of shares of common stock outstanding.

Dilution in net tangible book value per share represents the difference between the price per share of our common stock issued under securities purchase agreement and the adjusted net tangible book value per share of our common stock after giving effect to this offering of 1,497,006 shares of common stock, our adjusted net tangible book value per share of our common stock at September 30, 2020 would have been approximately $1.43 per share of common stock. This represents an immediate increase in net tangible book value per share of our common stock of approximately $0.42 per share to existing stockholders and an immediate dilution of approximately $5.25 per share to the purchaser in this offering. The following table illustrates this per-share dilution:

The foregoing table is based on 16,620,908 shares of common stock outstanding at September 30, 2020, which excludes, as of that date:

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PLAN OF DISTRIBUTION

A.G.P./Alliance Global Partners, as lead placement agent, and The Benchmark Company, LLC, as co-placement agent, have agreed to act as the placement agents (the “Placement Agents”) in connection with this offering. The Placement Agents are not purchasing or selling any of the shares of our common stock offered by this prospectus supplement but will use their reasonable best efforts to arrange for the sale of the securities offered by this prospectus supplement. We have entered into a securities purchase agreement directly with the Purchasers in connection with this offering. We will make offers only to a limited number of accredited investors. The offering is expected to close on or about March 3, 2021, subject to customary closing conditions, without further notice to you.

Fees and Expenses

We have agreed to pay the Placement Agents an aggregate Placement Agents’ fee of approximately $700,000.01, or 7% of the aggregate purchase price of the shares of our common stock sold in this offering. The following table shows the per share and total cash Placement Agents’ fees we will pay to the Placement Agents in connection with the sale of the shares of our common stock offered pursuant to this prospectus supplement and the accompanying prospectus.

In addition, we have agreed to reimburse the Placement Agents’ expenses up to $40,000 upon closing the offering. We estimate that the total expenses of the offering payable by us will be approximately $765,000 including the Placement Agents’ fees.

Regulation M

The Placement Agents may be deemed to be underwriters within the meaning of Section 2(a)(11) of the Securities Act and any commissions received by them and any profit realized on the resale of the shares sold by them while acting as principals might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, each Placement Agent would be required to comply with the requirements of the Securities Act and the Securities and Exchange Act of 1934 (the “Exchange Act”), including, without limitation, Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of shares by the Placement Agents acting as principals. Under these rules and regulations, the Placement Agents:

S-13

Indemnification

We have agreed to indemnify the Placement Agents and other specified persons against certain civil liabilities, including liabilities under the Securities Act and the Exchange Act, and to contribute to payments that the Placement Agents may be required to make in respect of such liabilities.

Lock-Up Agreement

We have agreed, subject to specified exceptions, that until 90 days after the closing date of the offering, neither we nor our subsidiary will issue, enter into any agreement to issue or announce the issuance or proposed issuance of any shares of common stock or any other securities that are convertible into, or exercisable or exchangeable for, or otherwise entitle the holder thereof to receive common stock, without the prior written consent of the Placement Agents or the investors participating in the offering. The Placement Agents may, in their sole discretion and at any time or from time to time before the termination of the 90-day period release us from all or any portion of this lock-up restriction.

Other Activities and Relationships

The Placement Agents and certain of their affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The Placement Agents and certain of their affiliates have, from time to time, performed, and may in the future perform, various commercial and investment banking and financial advisory services for us and our affiliates, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the Placement Agents and certain of its affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments issued by us and our affiliates. If the Placement Agents or their respective affiliates have a lending relationship with us, they routinely hedge their credit exposure to us consistent with their customary risk management policies. The Placement Agents and their respective affiliates may hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities. Any such short positions could adversely affect future trading prices of the shares offered hereby. The Placement Agents and certain of their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

The foregoing includes a brief summary of certain provisions of the placement agency agreement and securities purchase agreement that we will enter into and does not purport to be a complete statement of their terms and conditions. A copy of the placement agency agreement and the form of securities purchase agreement will be filed with the SEC and incorporated by reference into the registration statement of which this prospectus supplement forms a part. See “Where You Can Find More Information” on page S-15.

NASDAQ Capital Market Listing

Our common stock is listed on The NASDAQ Capital Market under the symbol “OSS.”

S-14

LEGAL MATTERS

The validity of the issuance of shares of common stock offered hereby has been passed upon for us by Procopio, Cory, Hargreaves & Savitch LLP, San Diego, California. Certain legal matters will be passed upon for the Placement Agents by Gracin & Marlow LLP New York, New York.

EXPERTS

The consolidated financial statements of One Stop Systems, Inc. as of December 31, 2019 and 2018, and for each of the years then ended, incorporated by reference in this prospectus supplement, have been so incorporated in reliance on the report of Haskell & White LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities being offered under this prospectus supplement. This prospectus supplement and accompanying prospectus, which forms part of the registration statement, does not contain all of the information in the registration statement. We have omitted certain parts of the registration statement, as permitted by the rules and regulations of the SEC. For further information regarding us and our securities, please see the registration statement and our other filings with the SEC, including our annual, quarterly, and current reports and any proxy statements, which are available to the public on the SEC’s Internet website at http://www.sec.gov.

We furnish holders of our common stock with annual reports containing audited financial statements prepared in accordance with accounting principles generally accepted in the United States following the end of each fiscal year. We file reports and other information with the SEC pursuant to the reporting requirements of the Exchange Act. In addition, the reports, proxy statements and other information that we file with the SEC are available to you free of charge through the Investor Relations page of our website, www.onestopsystems.com, as soon as reasonably practicable after they have been electronically filed with, or furnished to, the SEC. We have included our website address as a textual reference and do not intend it as an active link to our website. The contents of our website are not part of this prospectus supplement, and you should not consider the contents of our website in making an investment decision with respect to our securities.

Descriptions in this prospectus supplement and accompanying prospectus of documents are intended to be summaries of the material, relevant portions of those documents, but may not be complete descriptions of those documents. For complete copies of those documents, please refer to the exhibits to the registration statement and other documents filed by us with the SEC.

INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with the SEC, which means that we can disclose important information to you by referring you to those other documents. The information incorporated by reference is an important part of this prospectus supplement, and information we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14, or 15(d) of the Exchange Act prior to the termination of any offering of securities made by this prospectus:

S-15

Nothing in this prospectus supplement shall be deemed to incorporate information furnished but not filed with the SEC pursuant to Item 2.02 or Item 7.01 of Form 8-K.

Upon written or oral request, we will provide without charge to each person, including any beneficial owner, to whom this prospectus supplement is delivered, a copy of any or all of such information that has been incorporated herein by reference (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into the documents that this prospectus supplement incorporates). Written or oral requests for copies should be directed to One Stop Systems, Inc., Attn: Secretary, 2235 Enterprise Street #110, Escondido, California 92029, telephone number (877) 438-2724. See the section of this prospectus entitled “Where You Can Find More Information” for information concerning how to read and obtain copies of materials that we file with the SEC.

Any statement contained in this prospectus supplement, or in a document all or a portion of which is incorporated by reference, shall be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement, any future prospectus supplement or any document incorporated by reference modifies or supersedes such statement. Any such statement so modified or superseded shall not, except as so modified or superseded, constitute a part of this prospectus supplement.

S-16

PROSPECTUS

$100,000,000

Common Stock, Preferred Stock,

Debt Securities, Warrants, Subscription Rights and Units

From time to time, we may offer up to $100,000,000 aggregate dollar amount of shares of our common stock or preferred stock, debt securities, warrants to purchase our common stock, preferred stock or debt securities, subscription rights to purchase our common stock, preferred stock or debt securities and/or units consisting of some or all of these securities, in any combination, together or separately, in one or more offerings, in amounts, at prices and on the terms that we will determine at the time of the offering and which will be set forth in a prospectus supplement and any related free writing prospectus.

This prospectus describes the general manner in which those securities may be offered using this prospectus. Each time we offer securities, we will specify in an accompanying prospectus supplement and any related free writing prospectus the terms of securities offered and the offering thereof and may also add, update or change information contained in this prospectus.

The aggregate market value of our outstanding common stock held by non-affiliates was approximately $22.7 million, which was calculated based on 9,762,341 shares of outstanding common stock held by non-affiliates as of April 30, 2019, and a price per share of $2.33, the closing price of our common stock on April 30, 2019. Pursuant to General Instruction I.B.6 of Form S-3, in no event will we sell securities pursuant to this registration statement with a value more than one-third of the aggregate market value of our common stock held by non-affiliates in any 12-month period, so long as the aggregate market value of our common stock held by non-affiliates is less than $75.0 million. In the event that subsequent to the effective date of this registration statement, the aggregate market value of our outstanding common stock held by non-affiliates equals or exceeds $75.0 million, then the one-third limitation on sales shall not apply to additional sales made pursuant to this registration statement. We have not sold any securities pursuant to General Instruction I.B.6 of Form S-3 during the 12 calendar months prior to, and including, the date of this registration statement.

You should read this prospectus, the information incorporated, or deemed to be incorporated, by reference in this prospectus, and any applicable prospectus supplement and related free writing prospectus carefully before you invest.

Our common stock is traded on the Nasdaq Capital Market under the symbol “OSS.” On April 30, 2019, the last reported sales price for our common stock on the Nasdaq Capital Market was $2.33 per share. None of the other securities we may offer are currently traded on any securities exchange. The applicable prospectus supplement and any related free writing prospectus will contain information, where applicable, as to any other listing on the Nasdaq Capital Market or any securities market or exchange of the securities covered by the prospectus supplement and any related free writing prospectus.

An investment in our securities involves a high degree of risk. You should carefully consider the information under the heading “Risk Factors” beginning on page 7 of this prospectus and any applicable prospectus supplement, before investing in our securities.

The securities described in this prospectus may be sold to or through underwriters or dealers, directly to purchasers or through agents designated from time to time. For additional information on the methods of sale, you should refer to the section entitled “Plan of Distribution” in this prospectus. If any underwriters, dealers or agents are involved in the sale of any securities with respect to which this prospectus is being delivered, the names of such underwriters or agents and any applicable fees, discounts or commissions, details regarding over-allotment options, if any, will be set forth in a prospectus supplement. The price to the public of such securities and the net proceeds we expect to receive from such sale will also be set forth in a prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is June 19, 2019

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or SEC, using a “shelf” registration process. Under this shelf registration process, from time to time, we may sell any combination of the securities described in this prospectus in one or more offerings, up to an aggregate dollar amount of $100,000,000, subject to any applicable limits prescribed by General Instruction I.B.6 of Form S-3. Each time we sell securities under this shelf registration process, we will provide a prospectus supplement that will contain specific information about the terms of the offering. We have provided to you in this prospectus a general description of the securities we may offer.

We may also add, update or change in a prospectus supplement any of the information contained in this prospectus. To the extent there is a conflict between the information contained in this prospectus and any applicable prospectus supplement, you should rely on the information in such prospectus supplement; provided that, if any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in this prospectus or any prospectus supplement—the statement in the document having the later date modifies or supersedes the earlier statement. You should read both this prospectus and any prospectus supplement together with additional information described under the next heading “Where You Can Find More Information.”

You should rely only on the information contained in or incorporated by reference into this prospectus or any applicable prospectus supplement. No dealer, salesperson or any other person is authorized to give any information or to make any representation other than the information and representations contained in or incorporated by reference into this prospectus or any applicable prospectus supplement. If different information is given or different representations are made, you may not rely on that information or those representations as having been authorized by us. You may not imply from the delivery of this prospectus and any applicable prospectus supplement, nor from a sale made under this prospectus and any applicable prospectus supplement, that our affairs are unchanged since the date of this prospectus and any applicable prospectus supplement or that the information contained in any document incorporated by reference is accurate as of any date other than the date of the document incorporated by reference, regardless of the time of delivery of this prospectus and any applicable prospectus supplement or any sale of a security. This prospectus and any applicable prospectus supplement may only be used where it is legal to sell the securities.

In this prospectus, unless the context otherwise requires, the terms “One Stop,” “OSS,” the “Company,” “we,” “us,” and “our” refer to One Stop Systems, Inc., a Delaware corporation.

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RISK FACTORS

An investment in our securities involves a high degree of risk. The prospectus supplement relating to a particular offering of securities will contain a discussion of the risks applicable to an investment in the securities offered. Prior to making a decision about investing in our securities, you should carefully consider the specific factors discussed under the heading “Risk Factors” in the applicable prospectus supplement, together with all of the other information contained or incorporated by reference in the prospectus supplement or appearing or incorporated by reference in this prospectus. You should also consider the risks, uncertainties and assumptions discussed under Part I, Item 1A, “Risk Factors,” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2018, which is incorporated herein by reference, and may be amended, supplemented or superseded from time to time by other reports we file with the SEC in the future. The risks and uncertainties we have described are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our operations.

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FORWARD-LOOKING STATEMENTS

This prospectus and documents incorporated herein by reference contain “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements involve a number of risks and uncertainties. We caution readers that any forward-looking statement is not a guarantee of future performance and that actual results could differ materially from those contained in the forward-looking statement. These statements are based on current expectations of future events. Such statements include, but are not limited to, statements about future financial and operating results, plans, objectives, expectations and intentions, costs and expenses, interest rates, outcome of contingencies, financial condition, results of operations, liquidity, cost savings, objectives of management, business strategies, debt financing, clinical trial timing and plans, the achievement of clinical and commercial milestones, the advancement of our technologies and our product candidates, and other statements that are not historical facts. You can find many of these statements by looking for words like “believes,” “expects,” “anticipates,” “estimates,” “may,” “might,” “should,” “will,” “could,” “plan,” “intend,” “project,” “seek” or similar expressions in this prospectus or in documents incorporated by reference into this prospectus. We intend that such forward-looking statements be subject to the safe harbors created thereby.

These forward-looking statements are based on the current beliefs and expectations of our management and are subject to significant risks and uncertainties. If underlying assumptions prove inaccurate or unknown risks or uncertainties materialize, actual results may differ materially from current expectations and projections. Factors that might cause such a difference include those discussed in Part I, Item 1A “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2018, as well as those discussed in this prospectus and in the documents incorporated by reference into this prospectus. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this prospectus or, in the case of documents referred to or incorporated by reference, the date of those documents.

All subsequent written or oral forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section. We do not undertake any obligation to release publicly any revisions to these forward-looking statements to reflect events or circumstances after the date of this prospectus or to reflect the occurrence of unanticipated events, except as may be required under applicable U.S. securities law. If we do update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and are required to file annual, quarterly and other reports, proxy statements and other information with the SEC. You may inspect and copy these reports, proxy statements and other information at the public reference facilities maintained by the SEC in Washington, D.C., 100 F Street N.E., Washington, D.C. 20549. Copies of such materials can be obtained from the SEC’s public reference section at prescribed rates. You may obtain information on the operation of the public reference rooms by calling the SEC at (800) SEC-0330. Additionally, the SEC maintains an Internet site (www.sec.gov) that contains reports, proxy and information statements, and various other information about us. You may also inspect the documents described herein at our headquarters, 2235 Enterprise Street #110, Escondido, California 92029, during normal business hours.

Information about us is also available at our website at www.onestopsystems.com. However, the information on our website is not a part of this prospectus and is not incorporated by reference into this prospectus.

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INCORPORATION OF INFORMATION BY REFERENCE

The SEC allows us to “incorporate by reference” information that we file with the SEC, which means that we can disclose important information to you by referring you to those other documents. The information incorporated by reference is an important part of this prospectus, and information we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14, or 15(d) of the Exchange Act prior to the termination of any offering of securities made by this prospectus:

Upon written or oral request, we will provide without charge to each person, including any beneficial owner, to whom this prospectus is delivered, a copy of any or all of such information that has been incorporated herein by reference (other than exhibits to such documents unless such exhibits are specifically incorporated by reference into the documents that this prospectus incorporates). Written or oral requests for copies should be directed to One Stop Systems, Inc., Attn: Chief Executive Officer, 2235 Enterprise Street #110, Escondido, California 92029, telephone number (877) 438-2724. See the section of this prospectus entitled “Where You Can Find More Information” for information concerning how to read and obtain copies of materials that we file with the SEC at the SEC’s public offices.

Any statement contained in this prospectus, or in a document all or a portion of which is incorporated by reference, shall be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any prospectus supplement or any document incorporated by reference modifies or supersedes such statement. Any such statement so modified or superseded shall not, except as so modified or superseded, constitute a part of this prospectus.

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USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds to us from the sale of our securities under this prospectus. Unless otherwise provided in the applicable prospectus supplement, we intend to use the net proceeds from the sale of securities under this prospectus for general corporate purposes, which may include funding research and development, increasing our working capital and acquisitions or investments in businesses, products or technologies that are complementary to our own. We will set forth in the prospectus supplement our intended use for the net proceeds received from the sale of any securities. Pending the application of the net proceeds, we intend to invest the net proceeds in short-term or long-term, investment-grade, interest-bearing securities.

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PLAN OF DISTRIBUTION

We may sell the securities covered by this prospectus to one or more underwriters for public offering and sale by them, and may also sell the securities to investors directly or through agents. We will name any underwriter or agent involved in the offer and sale of securities in the applicable prospectus supplement. We have reserved the right to sell or exchange securities directly to investors on our own behalf in jurisdictions where we are authorized to do so. We may distribute the securities from time to time in one or more transactions:

We may directly solicit offers to purchase the securities being offered by this prospectus. We may also designate agents to solicit offers to purchase the securities from time to time. We will name in a prospectus supplement any agent involved in the offer or sale of our securities. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis, and a dealer will purchase securities as a principal for resale at varying prices to be determined by the dealer.

If we utilize an underwriter in the sale of the securities being offered by this prospectus, we will execute an underwriting agreement with the underwriter at the time of sale and we will provide the name of any underwriter in the prospectus supplement that the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we, or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or commissions from the purchasers for whom they may act as agent.

We will provide in the applicable prospectus supplement any compensation we pay to underwriters, dealers, or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act of 1933, or the Securities Act, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against civil liabilities, including liabilities under the Securities Act, and to reimburse them for certain expenses. We may grant underwriters who participate in the distribution of our securities under this prospectus an option to purchase additional securities to cover any over-allotments in connection with the distribution.

The securities we offer under this prospectus may or may not be listed through the Nasdaq Capital Market any other securities exchange. To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the securities. This may include short sales of the securities, which involves the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover such short positions by making purchases in the open market or by exercising their option to purchase additional securities. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

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We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and they may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in these sale transactions will be an underwriter and will be identified in the applicable prospectus supplement. In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus. The financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

We will file a prospectus supplement to describe the terms of any offering of our securities covered by this prospectus. The prospectus supplement will disclose:

We will bear all or substantially all of the costs, expenses and fees in connection with the registration of our securities under this prospectus. The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business.

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DESCRIPTION OF CAPITAL STOCK

General

The following is a summary of the rights of our common stock and preferred stock, certain provisions of our certificate of incorporation and amended and restated bylaws, the investors’ rights agreement and of the General Corporation Law of the State of Delaware. For more detailed information, please see our certificate of incorporation, amended and restated bylaws and investors’ rights agreement, which are filed as exhibits to the registration statement of which this prospectus is a part, as well as the relevant provisions of the General Corporation Law of the State of Delaware. We reincorporated in the State of Delaware on December 14, 2017 prior to the closing of our initial public offering.

Our certificate of incorporation provide for one class of common stock. In addition, our certificate of incorporation authorizes shares of undesignated preferred stock, the rights, preferences and privileges of which may be designated from time to time by our board of directors.

Our authorized capital stock consists of 60,000,000 shares, all with a $0.0001 par value of per share, of which:

As of April 30, 2019, there were 14,370,592 shares of our common stock outstanding and held of record by 92 stockholders.

Common Stock

Voting Rights

Each share of common stock entitles the holder to one vote with respect to each matter presented to our stockholders on which the holders of common stock are entitled to vote, including the election of directors. Holders of our common stock do not have cumulative voting rights. Except in respect of matters relating to the election and removal of directors on our board of directors and as otherwise provided in our certificate of incorporation or required by law, all matters to be voted on by our stockholders must be approved by a majority of the shares present in person or by proxy at the meeting and entitled to vote on the subject matter. In the case of election of directors, all matters to be voted on by our stockholders must be approved by a plurality of the votes entitled to be cast by all shares of common stock. Accordingly, the holders of a majority of the outstanding shares of common stock entitled to vote in any election of directors can elect all of the directors standing for election, if they so choose, other than any directors that holders of any preferred stock we may issue may be entitled to elect.

Dividends

Subject to preferences that may apply to any shares of preferred stock outstanding at the time, the holders of our common stock will be entitled to share equally, identically and ratably in any dividends that our board of directors may determine to issue from time to time.

Liquidation Rights

In the event of any voluntary or involuntary liquidation, dissolution or winding up of our affairs, holders of our common stock would be entitled to share ratably in our assets that are legally available for distribution to stockholders after payment of our debts and other liabilities. If we have any preferred stock outstanding at such time, holders of the preferred stock may be entitled to distribution and/or liquidation preferences. In either such case, we must pay the applicable distribution to the holders of our preferred stock before we may pay distributions to the holders of our common stock.

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Other Rights

Our stockholders have no preemptive, conversion or other rights to subscribe for additional shares, and there are no redemption or sinking funds provisions applicable to the common stock. All outstanding shares are, and all shares offered by this prospectus will be, when sold, validly issued, fully paid and nonassessable. The rights, preferences and privileges of the holders of our common stock will be subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock that we may designate and issue in the future.

Preferred Stock

There are no shares of preferred stock outstanding. Under the terms of our certificate of incorporation, our board of directors has the authority, without further action by our stockholders, to issue up to 10,000,000 shares of preferred stock in one or more series, to establish from time to time the number of shares to be included in each such series, to fix the dividend, voting and other rights, preferences and privileges of the shares of each wholly unissued series and any qualifications, limitations or restrictions thereon, and to increase or decrease the number of shares of any such series, but not below the number of shares of such series then outstanding.

Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of the common stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring or preventing a change in our control and may adversely affect the market price of the common stock and the voting and other rights of the holders of common stock. We have no current plans to issue any shares of preferred stock.

Options

As of March 31, 2019, options to purchase 1,980,904 shares of our common stock were outstanding, of which 1,639,461 were vested and exercisable as of that date.

Restricted Stock Units

As of March 31, 2019, 308,750 Restricted Stock Units (RSUs) were outstanding, of which 0 were vested as of that date.

Warrants

As of March 31, 2019, 561,181 shares of common stock issuable upon the exercise of warrants were reserved for issuance. The warrants are currently exercisable and expire six-seven years from the effective date of the issuance of said warrant. The warrants may not be sold, transferred, assigned, pledged or hypothecated during this offering.

Registration Rights

Demand Registration Rights

If, the holders of at least 50% of the registrable securities request in writing that we effect a registration with respect to their shares in an offering with an anticipated aggregate offering price, net of underwriting discounts and commissions, of greater than $10,000,000, we may be required to register their shares. We are obligated to effect at most two registrations for the holders of registrable securities in response to these demand registration rights, subject to certain exceptions.

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If we become entitled under the Securities Act to register our shares on a registration statement on Form S-3 and a holder of registrable securities requests in writing that we register their shares for public resale on Form S-3, the price to the public of the offering is $500,000 or more, we will be required to provide notice to all holders of registrable securities and to use our best efforts to effect such registration; provided, however, that we will not be required to effect such a registration if we have already effected two registrations on Form S-3 for the holders of registrable securities.

If the holders requesting registration intend to distribute their shares by means of an underwriting, the underwriter of such offering will have the right to limit the numbers of shares to be underwritten for reasons related to the marketing of the shares.

Piggyback Registration Rights

If at any time following the closing of this offering we propose to register any shares of our common stock under the Securities Act, subject to certain exceptions, the holders of registrable securities will be entitled to notice of the registration and to include their shares of registrable securities in the registration. If our proposed registration involves an underwriting, the managing underwriter of such offering will have the right to limit the number of shares to be underwritten for reasons related to the marketing of the shares.

In August 2018, we entered into a Common Shareholder Piggyback Registration Rights Agreement with a stockholder as part of an agreement in the purchase of Concept Development Inc.

Expenses

Ordinarily, other than underwriting discounts and commissions, we will be required to pay all reasonable expenses incurred by us related to any registration effected pursuant to the exercise of these registration rights. These expenses may include all registration, filing and qualification fees, printer and accounting fees relating or apportionable thereto, and the reasonable fees and disbursements of one counsel for the selling security holders.

Termination of Registration Rights

The registration rights terminate upon the earlier of two years after the closing of this offering, or for any particular holder with registration rights, at such time following this offering when such holder may sell its shares pursuant to Rule 144(b)(1) under the Securities Act.

Anti-Takeover Effects of Delaware Law and Our Certificate of Incorporation and Bylaws

Some provisions of Delaware law, our certificate of incorporation and our amended and restated bylaws contain provisions that could make the following transactions more difficult: an acquisition of us by means of a tender offer; an acquisition of us by means of a proxy contest or otherwise; or the removal of our incumbent officers and directors. It is possible that these provisions could make it more difficult to accomplish or could deter transactions that stockholders may otherwise consider to be in their best interest or in our best interests, including transactions which provide for payment of a premium over the market price for our shares.

These provisions, summarized below, are intended to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of the increased protection of our potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging these proposals because negotiation of these proposals could result in an improvement of their terms.

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Undesignated Preferred Stock

The ability of our board of directors, without action by the stockholders, to issue up to 10,000,000 shares of undesignated preferred stock with voting or other rights or preferences as designated by our board of directors could impede the success of any attempt to change control of us. These and other provisions may have the effect of deferring hostile takeovers or delaying changes in control or management of our company.

Stockholder Meetings

Our amended and restated bylaws provide that a special meeting of stockholders may be called only by our chairman of the board of directors, chief executive officer or president, or by a resolution adopted by a majority of our board of directors.

Requirements for Advance Notification of Stockholder Nominations and Proposals

Our amended and restated bylaws establish advance notice procedures with respect to stockholder proposals to be brought before a stockholder meeting and the nomination of candidates for election as directors, other than nominations made by or at the direction of the board of directors or a committee of the board of directors.

Removal of Directors

Our certificate of incorporation provides that no member of our board of directors may be removed from office by our stockholders except for cause and, in addition to any other vote required by law, upon the approval of not less than two thirds of the total voting power of all of our outstanding voting stock then entitled to vote in the election of directors.

Stockholders Not Entitled to Cumulative Voting

Our certificate of incorporation does not permit stockholders to cumulate their votes in the election of directors. Accordingly, the holders of a majority of the outstanding shares of our common stock entitled to vote in any election of directors can elect all of the directors standing for election, if they choose, other than any directors that holders of our preferred stock may be entitled to elect.

Delaware Anti-Takeover Statute

We are subject to Section 203 of the Delaware General Corporation Law, which prohibits persons deemed to be “interested stockholders” from engaging in a “business combination” with a publicly held Delaware corporation for three years following the date these persons become interested stockholders unless the business combination is, or the transaction in which the person became an interested stockholder was, approved in a prescribed manner or another prescribed exception applies. Generally, an “interested stockholder” is a person who, together with affiliates and associates, owns, or within three years prior to the determination of interested stockholder status did own, 15% or more of a corporation’s voting stock. Generally, a “business combination” includes a merger, asset or stock sale, or other transaction resulting in a financial benefit to the interested stockholder. The existence of this provision may have an anti-takeover effect with respect to transactions not approved in advance by the board of directors.

Choice of Forum

Our certificate of incorporation provides that, unless we consent in writing to the selection of an alternative form, the Court of Chancery of the State of Delaware will be the sole and exclusive forum for: (1) any derivative action or proceeding brought on our behalf; (2) any action asserting a claim of breach of a fiduciary duty or other wrongdoing by any of our directors, officers, employees or agents to us or our stockholders; (3) any action

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asserting a claim against us arising pursuant to any provision of the General Corporation Law of the State of Delaware or our certificate of incorporation or bylaws; (4) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or bylaws; or (5) any action asserting a claim governed by the internal affairs doctrine. Our certificate of incorporation also provides that any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock will be deemed to have notice of and to have consented to this choice of forum provision. It is possible that a court of law could rule that the choice of forum provision contained in our certificate of incorporation is inapplicable or unenforceable if it is challenged in a proceeding or otherwise.

Amendment of Charter Provisions

The amendment of any of the above provisions, except for the provision making it possible for our board of directors to issue preferred stock, would require approval by holders of at least two thirds of the total voting power of all of our outstanding voting stock.

The provisions of Delaware law, our certificate of incorporation and our amended and restated bylaws could have the effect of discouraging others from attempting hostile takeovers and, as a consequence, they may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in the composition of our board of directors and management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Corporate Stock Transfer, Inc. The transfer agent and registrar’s address is 3200 Cherry Creek Drive South, Suite 430, Denver, CO 80209.

Exchange Listing

Our common stock is listed on The Nasdaq Capital Market under the symbol “OSS.”

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DESCRIPTION OF DEBT SECURITIES

General

We will issue the debt securities offered by this prospectus and any accompanying prospectus supplement under an indenture to be entered into between us and the trustee identified in the applicable prospectus supplement. The terms of the debt securities will include those stated in the indenture and those made part of the indenture by reference to the Trust Indenture Act of 1939, as in effect on the date of the indenture.

We may offer under this prospectus up to an aggregate principal amount of $100,000,000 in debt securities, or if debt securities are issued at a discount, or in a foreign currency, foreign currency units or composite currency, the principal amount as may be sold for an aggregate public offering price of up to $100,000,000. Unless otherwise specified in the applicable prospectus supplement, the debt securities will represent our direct, unsecured obligations and will rank equally with all of our other unsecured indebtedness.

We may issue the debt securities in one or more series with the same or various maturities, at par, at a premium, or at a discount. We will describe the particular terms of each series of debt securities in a prospectus supplement relating to that series, which we will file with the SEC. The prospectus supplement relating to the particular series of debt securities being offered will specify the particular amounts, prices and terms of those debt securities. These terms may include:

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We may issue discount debt securities that provide for an amount less than the stated principal amount to be due and payable upon acceleration of the maturity of such debt securities in accordance with the terms of the indenture. We may also issue debt securities in bearer form, with or without coupons. If we issue discount debt securities or debt securities in bearer form, we will describe material U.S. federal income tax considerations and other material special considerations which apply to these debt securities in the applicable prospectus supplement.

We may issue debt securities denominated in or payable in a foreign currency or currencies or a foreign currency unit or units. If we do, we will describe the restrictions, elections, and general tax considerations relating to the debt securities and the foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Debt securities offered under this prospectus and any prospectus supplement will be subordinated in right of payment to certain of our outstanding senior indebtedness, including our credit facilities. In addition, we will seek the consent of the holders of any such senior indebtedness prior to issuing any debt securities under this prospectus to the extent required by the agreements evidencing such senior indebtedness.

Registrar and Paying Agent

The debt securities may be presented for registration of transfer or for exchange at the corporate trust office of the security registrar or at any other office or agency that we maintain for those purposes. In addition, the debt securities may be presented for payment of principal, interest and any premium at the office of the paying agent or at any office or agency that we maintain for those purposes.

Conversion or Exchange Rights

Debt securities may be convertible into or exchangeable for shares of our common stock. The terms and conditions of conversion or exchange will be stated in the applicable prospectus supplement. The terms will include, among others, the following:

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Registered Global Securities

If we decide to issue debt securities in the form of one or more global securities, then we will register the global securities in the name of the depositary for the global securities or the nominee of the depositary, and the global securities will be delivered by the trustee to the depositary for credit to the accounts of the holders of beneficial interests in the debt securities.

The prospectus supplement will describe the specific terms of the depositary arrangement for debt securities of a series that are issued in global form. None of us, the trustee, any payment agent or the security registrar will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a global debt security or for maintaining, supervising or reviewing any records relating to these beneficial ownership interests.

No Protection in the Event of Change of Control

The indenture does not have any covenants or other provisions providing for a put or increased interest or otherwise that would afford holders of our debt securities additional protection in the event of a recapitalization transaction, a change of control or a highly leveraged transaction. If we offer any covenants or provisions of this type with respect to any debt securities covered by this prospectus, we will describe them in the applicable prospectus supplement.

Covenants

Unless otherwise indicated in this prospectus or the applicable prospectus supplement, our debt securities will not have the benefit of any covenants that limit or restrict our business or operations, the pledging of our assets or the incurrence by us of indebtedness. We will describe in the applicable prospectus supplement any material covenants in respect of a series of debt securities.

Merger, Consolidation or Sale of Assets

The form of indenture provides that we will not consolidate with or merge into any other person or convey, transfer, sell or lease our properties and assets substantially as an entirety to any person, unless:

Events of Default

Unless otherwise specified in the applicable prospectus supplement, the following events will be events of default under the indenture with respect to debt securities of any series:

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The trustee may withhold notice to the holders of the debt securities of any series of any default, except in payment of principal of or premium, if any, or interest on the debt securities of a series, if the trustee considers it to be in the best interest of the holders of the debt securities of that series to do so.

If an event of default (other than an event of default resulting from certain events of bankruptcy, insolvency or reorganization) occurs, and is continuing, then the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding debt securities of any series may accelerate the maturity of the debt securities. If this happens, the entire principal amount, plus the premium, if any, of all the outstanding debt securities of the affected series plus accrued interest to the date of acceleration will be immediately due and payable. At any time after the acceleration, but before a judgment or decree based on such acceleration is obtained by the trustee, the holders of a majority in aggregate principal amount of outstanding debt securities of such series may rescind and annul such acceleration if:

In addition, if the acceleration occurs at any time when we have outstanding indebtedness that is senior to the debt securities, the payment of the principal amount of outstanding debt securities may be subordinated in right of payment to the prior payment of any amounts due under the senior indebtedness, in which case the holders of debt securities will be entitled to payment under the terms prescribed in the instruments evidencing the senior indebtedness and the indenture.

If an event of default resulting from certain events of bankruptcy, insolvency or reorganization occurs, the principal, premium and interest amount with respect to all of the debt securities of any series will be due and payable immediately without any declaration or other act on the part of the trustee or the holders of the debt securities of that series.

The holders of a majority in principal amount of the outstanding debt securities of a series will have the right to waive any existing default or compliance with any provision of the indenture or the debt securities of that series and to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, subject to certain limitations specified in the indenture.

No holder of any debt security of a series will have any right to institute any proceeding with respect to the indenture or for any remedy under the indenture, unless:

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These limitations do not, however, apply to a suit instituted for payment on debt securities of any series on or after the due dates expressed in the debt securities.

We will periodically deliver certificates to the trustee regarding our compliance with our obligations under the indenture.

Modification and Waiver

From time to time, we and the trustee may, without the consent of holders of the debt securities of one or more series, amend the indenture or the debt securities of one or more series, or supplement the indenture, for certain specified purposes, including:

From time to time we and the trustee may, with the consent of holders of at least a majority in principal amount of an outstanding series of debt securities, amend or supplement the indenture or the debt securities series, or waive compliance in a particular instance by us with any provision of the indenture or the debt securities. We may not, however, without the consent of each holder affected by such action, modify or supplement the indenture or the debt securities or waive compliance with any provision of the indenture or the debt securities in order to:

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Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

The indenture permits us, at any time, to elect to discharge our obligations with respect to one or more series of debt securities by following certain procedures described in the indenture. These procedures will allow us either:

In order to exercise either defeasance option, we must deposit with the trustee or other qualifying trustee, in trust for that

that, in each case specified above, provides a sufficient amount to pay the principal of, premium, if any, and interest, if any, on the debt securities of the series, on the scheduled due dates or on a selected date of redemption in accordance with the terms of the indenture.

In addition, defeasance may be effected only if, among other things:

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If we fail to comply with our remaining obligations under the indenture and applicable supplemental indenture after a covenant defeasance of the indenture and applicable supplemental indenture, and the debt securities are declared due and payable because of the occurrence of any undefeased event of default, the amount of money and/or U.S. Government Obligations and/or Foreign Government Obligations on deposit with the trustee could be insufficient to pay amounts due under the debt securities of the affected series at the time of acceleration. We will, however, remain liable in respect of these payments.

The term “U.S. Government Obligations” as used in the above discussion means securities that are direct obligations of or non-callable obligations guaranteed by the United States of America for the payment of which obligation or guarantee the full faith and credit of the United States of America is pledged.

The term “Foreign Government Obligations” as used in the above discussion means, with respect to debt securities of any series that are denominated in a currency other than U.S. dollars, (1) direct obligations of the government that issued or caused to be issued such currency for the payment of which obligations its full faith and credit is pledged or (2) obligations of a person controlled or supervised by or acting as an agent or instrumentality of such government the timely payment of which is unconditionally guaranteed as a full faith and credit obligation by that government, which in either case under clauses (1) or (2), are not callable or redeemable at the option of the issuer.

Regarding the Trustee

We will identify the trustee with respect to any series of debt securities in the prospectus supplement relating to the applicable debt securities. You should note that if the trustee becomes a creditor of ours, the indenture and the Trust Indenture Act of 1939 limit the rights of the trustee to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim, as security or otherwise. The trustee and its affiliates may engage in, and will be permitted to continue to engage in, other transactions with us and our affiliates. If, however, the trustee acquires any “conflicting interest” within the meaning of the Trust Indenture Act of 1939, it must eliminate such conflict or resign.

The holders of a majority in principal amount of the then outstanding debt securities of any series may direct the time, method and place of conducting any proceeding for exercising any remedy available to the trustee. If an event of default occurs and is continuing, the trustee, in the exercise of its rights and powers, must use the degree of care and skill of a prudent person in the conduct of his or her own affairs. Subject to that provision, the trustee will be under no obligation to exercise any of its rights or powers under the indenture at the request of any of the holders of the debt securities, unless they have offered to the trustee reasonable indemnity or security.

No Individual Liability of Incorporators, Stockholders, Officers or Directors

Each indenture provides that no incorporator and no past, present or future stockholder, officer or director of our company or any successor corporation in those capacities will have any individual liability for any of our obligations, covenants or agreements under the debt securities or such indenture.

Governing Law

The indentures and the debt securities will be governed by, and construed in accordance with, the laws of the State of Delaware.

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DESCRIPTION OF WARRANTS

General

We may issue warrants for the purchase of our debt securities, preferred stock, common stock, or any combination thereof. Warrants may be issued independently or together with our debt securities, preferred stock or common stock and may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent. The warrant agent will act solely as our agent in connection with the warrants. The warrant agent will not have any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants. This summary of certain provisions of the warrants is not complete. For the terms of a particular series of warrants, you should refer to the prospectus supplement for that series of warrants and the warrant agreement for that particular series.

Debt Warrants

The prospectus supplement relating to a particular issue of warrants to purchase debt securities will describe the terms of the debt warrants, including the following:

Debt warrant certificates will be exchangeable for new debt warrant certificates of different denominations. Debt warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in

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the prospectus supplement. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the debt securities purchasable upon exercise and will not be entitled to payment of principal or any premium, if any, or interest on the debt securities purchasable upon exercise.

Equity Warrants

The prospectus supplement relating to a particular series of warrants to purchase our common stock or preferred stock will describe the terms of the warrants, including the following:

Holders of equity warrants will not be entitled:

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DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase our common stock, preferred stock or debt securities. These subscription rights may be offered independently or together with any other security offered hereby and may or may not be transferable by the stockholder receiving the subscription rights in such offering. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights we offer, if any, will, to the extent applicable, include specific terms relating to the offering, including some or all of the following:

The description in the applicable prospectus supplement of any subscription rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate, which will be filed with the SEC if we offer subscription rights. We urge you to read the applicable subscription rights certificate and any applicable prospectus supplement in their entirety.

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DESCRIPTION OF UNITS

We may issue units consisting of some or all of the securities described above, in any combination, including common stock, preferred stock, warrants and/or debt securities. The terms of these units will be set forth in a prospectus supplement. The description of the terms of these units in the related prospectus supplement will not be complete. You should refer to the applicable form of unit and unit agreement for complete information with respect to these units.

LEGAL MATTERS

Procopio, Cory, Hargreaves & Savitch LLP, San Diego, California, will issue an opinion about certain legal matters with respect to the securities. Any underwriters or agents will be advised about legal matters relating to any offering by their own counsel.

EXPERTS

The consolidated financial statements of One Stop Systems, Inc. as of December 31, 2018 and 2017, and for each of the years then ended, incorporated by reference in this prospectus, have been so incorporated in reliance on the report of Haskell & White LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

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1,497,006 Shares of Common Stock

PROSPECTUS SUPPLEMENT

Lead Placement Agent

A.G.P.

Co-Placement Agent

The Benchmark Company, LLC

March 1, 2021