# EDGAR Filing Document

**Accession Number:** 0001605888
**File Stem:** 0001213900-25-118830
**Filing Date:** 2025-12
**Character Count:** 161805
**Document Hash:** 9627fcbe02bf693e6ab0a1dcb29d65e3
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-25-118830.hdr.sgml**: 20251205

**ACCESSION NUMBER**: 0001213900-25-118830

**CONFORMED SUBMISSION TYPE**: S-3

**PUBLIC DOCUMENT COUNT**: 15

**FILED AS OF DATE**: 20251205

**DATE AS OF CHANGE**: 20251205

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ATLANTIC INTERNATIONAL CORP.
- **CENTRAL INDEX KEY:** 0001605888
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-HELP SUPPLY SERVICES [7363]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 465319744
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-3
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-291991
- **FILM NUMBER:** 251553905

**BUSINESS ADDRESS:**
- **STREET 1:** 270 SYLVAN AVENUE
- **STREET 2:** SUITE 2230
- **CITY:** ENGLEWOOD CLIFFS
- **STATE:** NJ
- **ZIP:** 07632
- **BUSINESS PHONE:** 2018994470

**MAIL ADDRESS:**
- **STREET 1:** 270 SYLVAN AVENUE
- **STREET 2:** SUITE 2230
- **CITY:** ENGLEWOOD CLIFFS
- **STATE:** NJ
- **ZIP:** 07632

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** SeqLL, Inc.
- **DATE OF NAME CHANGE:** 20140417

**AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON DECEMBER 5, 2025**

**Registration Statement No. 333-[___]**

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, D.C. 20549**

**FORM S-3**

**REGISTRATION STATEMENT<br> UNDER**

**THE SECURITIES ACT OF 1933**

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| |
|:---|
| **ATLANTIC INTERNATIONAL CORP.** |
| *(Exact name of Registrant as specified in its Charter)* |

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| | |
|:---|:---|
| **Delaware** | **46-5319744** |
| *(State or other jurisdiction*<br> *of incorporation or organization)* | *(I.R.S. Employer*<br> *Identification No.)* |

---

**270 Sylvan Avenue, Suite 2230**

**Englewood Cliffs, NJ 07632**

**<u>(201) 899-4470</u>** 

*(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)*

**Jeffrey Jagid<br> Chief Executive Officer**

**270 Sylvan Avenue, Suite 2230**

**Englewood Cliffs, NJ 07632**

**<u>(201) 899-4470</u>**

*(Name, address, including zip code, and telephone number, including area code, of agent for service)*

*Copies to:*

**Elliot H. Lutzker, Esq.**

**Mark Goldenberg, Esq.<br> Davidoff Hutcher & Citron LLP<br> 605 Third Avenue, 34<sup>th</sup> Floor<br> New York, NY 10158<br> Telephone: (646) 428-3210<br> Fax: (212) 286-1884**

**Approximate date of commencement of proposed sale to public: From time to time after the effective date of this registration statement.**

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, please check the following box. ☒

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

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

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

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

Large accelerated filer ☐ Accelerated filer ☐ <br> Non-accelerated filer ☒ Smaller reporting company ☒ <br> Emerging Growth Company ☒

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

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

**EXPLANATORY NOTE**

This registration statement is a replacement registration statement being filed pursuant to Rule 415(a)(6) under the Securities Act of 1933, as amended (the "Securities Act"), with respect to securities that remain unsold under the registrant's Registration Statement on Form S-3 (File No. 333-268319), as amended, originally declared effective on December 8, 2022 (the "Prior Registration Statement"). Pursuant to Rule 415(a)(5)(ii) under the Securities Act, by filing this registration statement on Form S-3, the Company may issue and sell securities covered by the Prior Registration Statement until the earlier of (i) the effective date of this registration statement and (ii) June 6, 2026, which is 180 days after the third-year anniversary of the original effective date of the Prior Registration Statement. Pursuant to Rule 415(a)(6) under the Securities Act, the offering of securities under the Prior Registration Statement will be deemed terminated as of the date of effectiveness of this registration statement.

**The information in this prospectus is not complete and may be changed. We may not sell these securities, or accept an offer to buy these securities, until the Registration Statement filed with the Securities Exchange Commission, of which this prospectus is a part, is effective. This prospectus is not an offer to sell these securities and is not soliciting offers to buy these securities in any jurisdiction where the offer or sale is not permitted.**

**PRELIMINARY PROSPECTUS**

**SUBJECT TO COMPLETION: DATED DECEMBER 5, 2025**

**$250,000,000**

**ATLANTIC INTERNATIONAL CORP.**

**Shares of Common Stock**

**Shares of Preferred Stock**

**Senior Debt Securities**

**Subordinated Debt Securities**

**Units**

**Subscription Rights**

We may offer from time-to-time shares of our common stock, preferred stock, senior debt securities (which may be convertible into or exchangeable for common stock), subordinated debt securities (which may be convertible into or exchangeable for common stock), warrants, subscription rights and units that include any of these securities. The aggregate initial offeringprice of the securities sold under this prospectus will not exceed $250,000,000. We will offer the securities in amounts, at prices and on terms to be determined at the time of the offering.

Our common stock is listed on the Nasdaq Global Market under the symbol "ATLN." On December 4, 2025, the last reported sale price prior to the date of this prospectus, of the common stock on the Nasdaq Global Market was $2.28. The Shares may be sold at prevailing market prices or privately negotiated prices or in transactions that are not in the public market.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering and the amounts, prices and terms of the securities. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus, the applicable prospectus supplement, as well as the documents incorporated or deemed to be incorporated by reference herein or therein, before you purchase any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. These securities also may be resold by selling securityholders. If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in an applicable prospectus supplement. See the sections of this prospectus entitled "About this Prospectus" and "Plan of Distribution" for further information.

No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

**Investing in our securities is highly speculative and involves a high degree of risk. You should carefully read and consider the "Risk Factors" beginning on page 9 of this prospectus before investing.**

**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 ____________ [ ], 2025.

We are an "emerging growth company" and a "smaller reporting company" under the federal securities laws and, as such, we have elected to comply with certain reduced public company reporting requirements for this prospectus supplement. See "Prospectus Supplement Summary—Implications of Being an Emerging Growth Company and a Smaller Reporting Company."

**Investing in our common stock involves a high degree of risk. See "<u>Risk Factors</u>" beginning on page S-4 of the prospectus supplement, and under similar headings in the other documents that are incorporated by reference into this prospectus supplement concerning factors you should consider before investing in our common stock.**

**Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying base prospectus. Any representation to the contrary is a criminal offense.**

**TABLE OF CONTENTS**

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| | |
|:---|:---|
| **EXPLANATORY NOTE** |  |
| [**ABOUT THIS PROSPECTUS**](#k_002) | ii |
| [**CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS**](#k_003) | iii |
| [**WHERE YOU CAN FIND MORE INFORMATION, INCORPORATION BY REFERENCE**](#k_004) | iv |
| [**PROSPECTUS SUMMARY**](#k_005) | 1 |
| [**USE OF PROCEEDS**](#k_006) | 3 |
| [**PLAN OF DISTRIBUTION**](#k_007) | 3 |
| [**DESCRIPTION OF SECURITIES**](#k_008) | 5 |
| [**DESCRIPTION OF COMMON STOCK**](#k_009) | 5 |
| [**DESCRIPTION OF PREFERRED STOCK**](#k_010) | 7 |
| [**DESCRIPTION OF DEBT SECURITIES**](#k_011) | 8 |
| [**DESCRIPTION OF WARRANTS**](#k_012) | 10 |
| [**DESCRIPTION OF RIGHTS**](#k_013) | 12 |
| [**DESCRIPTION OF UNITS**](#k_014) | 13 |
| [**DIVIDEND POLICY**](#k_015) | 14 |
| [**LEGAL MATTERS**](#k_016) | 14 |
| [**EXPERTS**](#k_017) | 14 |

---

i

**ABOUT THIS PROSPECTUS**

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission, or the SEC, using a "shelf" registration process. Under this shelf registration process, we may sell shares of Common Stock, Preferred Stock (including convertible preferred shares), Senior Debt Securities, Convertible Debt Securities, warrants for equity securities, units and subscription rights comprised of any combination thereof from time to time in one or more offerings for up to an initial aggregate offering price of $250,000,000. By using a shelf registration statement, we may sell securities from time to time and in one or more offerings as described in this prospectus. This prospectus provides you with a general description of the securities we may offer. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the securities being offered and sold and the specific terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. In each prospectus supplement, we will include the following information:

● the number and type of securities that we propose to sell;

● the public offering price;

● the names of any underwriters, agents or dealers through or to which the securities will be sold;

● any compensation of those underwriters, agents or dealers;

● any additional risk factors applicable to the securities or our business and operations; and

● any other material information about the offering and sale of the securities.

If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement or free writing prospectus, you should rely on the prospectus supplement or free writing prospectus, as applicable. However, no prospectus supplement will offer a security that is not registered and described in this prospectus at the time of its effectiveness. This prospectus, together with the applicable prospectus supplement and the documents incorporated by reference into this prospectus, includes all material information relating to the offering of securities under this prospectus. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement (and any applicable free writing prospectuses), the information and documents incorporated herein by reference and the additional information described under the heading "Where You Can Find More Information; Incorporation by Reference."

**This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement**.

You should rely only on the information contained in or incorporated by reference in this prospectus, any related free-writing prospectus or any prospectus supplement. We have not authorized anyone to provide you with any information or to make any representations other than those contained in or incorporated by reference into this prospectus, any applicable prospectus supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate only as of the date on its respective cover, that the information appearing in any applicable free writing prospectus is accurate only as of the date of that free writing prospectus, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates. This prospectus incorporates by reference, and any prospectus supplement or free writing prospectus may contain and incorporate by reference, market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. In addition, the market and industry data and forecasts that may be included or incorporated by reference in this prospectus, any prospectus supplement or any applicable free writing prospectus may involve estimates, assumptions and other risks and uncertainties and are subject to change based on various factors, including those discussed under the heading "Risk Factors" contained in our annual report on Form 10-K for the fiscal year ended December 31, 2024 under the heading "Part II - Item 1A. Risk Factors," and as described or may be described in any subsequent quarterly report on Form 10-Q or current report on Form 8-K, as well as in any applicable prospectus supplement and contained or to be contained in our filings with the SEC and incorporated by reference in this prospectus, together with all of the other information contained in this prospectus, or any applicable prospectus supplement. Accordingly, investors should not place undue reliance on this information.

No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus, applicable prospectus supplement or any related free writing prospectus.

These documents are not an offer to sell or a solicitation of an offer to buy these securities in any circumstances under which the offer or solicitation is unlawful, nor does this prospectus, any applicable supplement to this prospectus, or any applicable free writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction.

ii

**CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS**

This report contains "forward-looking statements" for purposes of the safe harbor provisions provided by Section 27 of the Securities Act of 1933, as amended (the "Securities Act") and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), that represent our beliefs, projections and predictions about future events. All statements other than statements of historical fact are "forward-looking statements," including any projections of earnings, revenue or other financial items, any statements of the plans, strategies and objectives of management for future operations, any statements concerning proposed new projects or other developments, any statements regarding future economic conditions or performance, any statements of management's beliefs, goals, strategies, intentions and objectives, and any statements of assumptions underlying any of the foregoing. Words such as "may," "will," "should," "could," "would," "predicts," "potential," "continue," "expects," "anticipates," "future," "intends," "plans," "believes," "estimates" and similar expressions, as well as statements in the future tense, identify forward-looking statements.

These statements are necessarily subjective and involve known and unknown risks, uncertainties and other important factors that could cause our actual results, performance or achievements, or industry results, to differ materially from any future results, performance or achievements described in or implied by such statements. Actual results may differ materially from expected results described in our forward-looking statements, including with respect to correct measurement and identification of factors affecting our business or the extent of their likely impact, and the accuracy and completeness of the publicly available information with respect to the factors upon which our business strategy is based or the success of our business.

Forward-looking statements should not be read as a guarantee of future performance or results, and will not necessarily be accurate indications of whether, or the times by which, our performance or results may be achieved. Forward-looking statements are based on information available at the time those statements are made and management's belief as of that time with respect to future events and are subject to risks and uncertainties that could cause actual performance or results to differ materially from those expressed in or suggested by the forward-looking statements. Important factors that could cause such differences include, but are not limited to, those factors discussed under the headings "Risk Factors," contained in our annual report on Form 10-K for the fiscal year ended December 31, 2024, and as described or may be described in any subsequent quarterly report on Form 10-Q, or current report on Form 8-K, as well as in any applicable prospectus supplement and contained or to be contained in our filings with the SEC and incorporated by reference in this prospectus, "Prospectus Summary," and elsewhere in this prospectus.

iii

**WHERE YOU CAN FIND MORE INFORMATION, INCORPORATION BY REFERENCE**

**Available Information**

We file annual reports, quarterly reports, current reports, proxy statements and other information with the Securities and Exchange Commission ("SEC"). You may read or obtain a copy of these reports at the SEC's public reference room at 100 F Street, N.E., Washington, D.C. 20549, on official business days during the hours of 10:00 am to 3:00 pm. You may obtain information on the operation of the public reference room and its copy charges by calling the SEC at 1-800-SEC-0330. The SEC maintains a website that contains registration statements, reports, proxy information statements and other information regarding registrants that file electronically with the SEC, which are available free of charge. The address of the website is http://www.sec.gov. If you do not have Internet access, requests for copies of such documents should be directed to Michael V. Tenore, the Company's General Counsel, at the Company's headquarters, located at 270 Sylvan Avenue, Suite 2230, Englewood Cliffs, NJ 07632.

Our website address is www. https://www.atlantic-international.com. The information on, or accessible through, our website, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement or documents incorporated by reference in the registration statement. Statements in this prospectus or any prospectus supplement about these documents are summaries, and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC's website, as provided above.

**Incorporation Of Certain Information by Reference**

We incorporate by reference into this prospectus additional documents (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits on such form that are related to such items) that we may file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the completion or termination of the offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information deemed furnished and not filed with the SEC.

This prospectus may contain information that updates, modifies or is contrary to information in one or more of the documents incorporated by reference in this prospectus. You should rely only on the information incorporated by reference or provided in this prospectus. We have not authorized anyone else to provide you with different information. You should not assume that the information in this prospectus is accurate as of any date other than the date of this prospectus, or the date of the documents incorporated by reference in this prospectus.

We will provide to each person, including any beneficial owner, to whom this prospectus is delivered, upon written or oral request, at no cost to the requester, a copy of any and all of the information that is incorporated by reference in this prospectus.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC since the end of the fiscal year ended December 31, 2024:

&nbsp;&nbsp;&nbsp;&nbsp;(1) Atlantic
International [Schedule 14A](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000041/atln-20250916.htm) Proxy Statement filed with the SEC on September 17, 2025, as amended;

&nbsp;&nbsp;&nbsp;&nbsp;(2) Atlantic
International Annual Report on [Form 10-K](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000006/altn-20241231.htm) filed with the SEC on March 28, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;(3) Atlantic
Quarterly Reports on Form 10-Q for the quarters ended [March 31, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000019/altn-20250331.htm) , [June 30, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000031/altn-20250630.htm) , and [September 30, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000055/altn-20250930.htm) filed with the SEC on May
14, 2025, August 14, 2025 and November 14, 2025, respectively;

&nbsp;&nbsp;&nbsp;&nbsp;(4) Current
reports on Form 8-K filed with the SEC on [January 13, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000121390025003018/ea0227522-8k_atlantic.htm) , [February 28, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000121390025018768/ea0232636-8k_atlantic.htm) , [May 5, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000010/altn-20250429.htm) , [August 11, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000027/altn-20250602.htm) , [October 31, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000043/altn-20251031.htm) and [November 10, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000050/altn-20251107.htm) , respectively; and

&nbsp;&nbsp;&nbsp;&nbsp;(5) The
descriptions of Atlantic International's common stock which is registered under Section 12 of the Exchange Act, in Atlantic International's
registration statement on [Form S-1](https://www.sec.gov/Archives/edgar/data/1605888/000121390024058504/ea0208755-s1_atlantic.htm) (No. 333-280653), filed on July 2, 2024, including any amendments or reports filed for the purpose
of updating such description.

You may request, and we will provide you with, a copy of these filings, at no cost, by contacting us at:

Atlantic International Corp.

270 Sylvan Avenue, Suite 2230

Englewood Cliffs, NJ

Attention: Corporate Secretary

Telephone: (201) 899-4470

iv

**PROSPECTUS SUMMARY**

 

*The following summary highlights information contained elsewhere in this prospectus. The summary may not contain all of the information that may be important to you. You should read this entre prospectus carefully, including our financial statements and related notes thereto and the documents incorporated by reference in this prospectus and the risks described below under "Risk factors." And as described or may be described in any subsequent quarterly report on Form 10-Q or Current Report on Form 8-K, as well as in any applicable prospectus supplement and contained or to be contained in our filings with the SEC and incorporated by reference in this prospectus. We note that our actual results and future events may differ significantly based upon a number of factors. The reader should not put undue reliance on the forward-looking statements in this document, which speak only as of the date on the cover of this prospectus.*

 

*In this prospectus, unless otherwise noted, the terms "the Company," "Atlantic," "we," "us," and "our" refer to Atlantic International Corp.*

 

**Overview**

Atlantic International Corp. ("Atlantic") (Nasdaq: ATLN), through its subsidiaries, is a national strategic staffing firm servicing the commercial, professional, finance, direct placement, and managed service provider verticals. Lyneer was formed under the principles of honesty and integrity, and with the view of becoming the preferred outside employer of choice. Since its formation, the Company has grown from a regional operation to a national staffing firm with offices and geographic reach across the United States. The Company primarily places individuals in accounting and finance, administrative and clerical, information technology, legal, light industrial, and medical roles. Atlantic's approximately 300 employees generated over $400 million in revenue for the year ended December 31, 2024.

**Corporate Information** 

We were incorporated in Delaware under the name SeqLL Inc. on April 1, 2014. On June 13, 2024, the Company changed its name from SeqLL Inc. to Atlantic International Corp. On June 4, 2024 the Company, SeqLL Merger LLC, a Delaware limited liability company and wholly-owned subsidiary of the Company ("Purchaser Sub"), Atlantic Acquisition Corp, a Delaware corporation "Atlantic", Atlantic Merger LLC, a Delaware limited liability company and a majority-owned subsidiary of Atlantic ("Atlantic Merger Sub"), Lyneer Investments, LLC, a Delaware limited liability company ("Lyneer"), and IDC Technologies, a California corporation ("IDC"), entered into the Merger Agreement pursuant to which (i) Atlantic Merger Sub was merged with and into Lyneer, with Lyneer continuing as the surviving entity and (ii) Purchaser Sub was merged with and into Lyneer with Lyneer continuing as the surviving entity and as a wholly-owned subsidiary of the Company, collectively by referred to as the Merger.

Our corporate headquarters are located at 270 Sylvan Avenue, Suite 2230, Englewood Cliffs, New Jersey 07632. Our main telephone number at that address is (201) 899-4470, and our website address is *www.atlantic-international.com*. The information on our website is not part of this prospectus. We have included our website address as a factual reference and do not intend it to be an active link to our website.

**Implications of Being an Emerging Growth Company and a Smaller Reporting Company**

We qualify as an "emerging growth company" as defined in the Jumpstart Our Business Startups Act of 2012, as amended, or the JOBS Act. As an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies.

These provisions include:

● being permitted to only disclose two years of audited financial statements in addition to any required unaudited interim financial statements with correspondingly reduced "Management's Discussion and Analysis of Financial Condition and Results of Operations" disclosure;

● reduced disclosure about our executive compensation arrangements;

● not being required to hold advisory votes on executive compensation or to obtain stockholder approval of any golden parachute arrangements not previously approved; and

● an exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting.

We may take advantage of these exemptions until the end of the fiscal year following the fifth anniversary of our initial public offering or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company on the date that is the earliest of (i) the last day of the fiscal year in which we have total annual gross revenue of $1.235 billion or more; (ii) December 31, 2025; (iii) the date on which we have issued more than $1.0 billion in nonconvertible debt during the previous three years; or (iv) the last day of the fiscal year in which we are deemed to be a large accelerated filer under the rules of the SEC, which means the market value of our common stock that is held by non-affiliates exceeds $700 million as of the prior June 30th. We may choose to take advantage of some but not all of these exemptions. We have taken advantage of reduced reporting requirements in this prospectus supplement. Accordingly, the information contained herein may be different from the information you receive from other public companies in which you hold stock.

We are also a "smaller reporting company" as defined in the Exchange Act. We may continue to be a smaller reporting company even after we are no longer an emerging growth company. We may take advantage of certain of the scaled disclosures available to smaller reporting companies until the fiscal year following the determination that our common stock held by non-affiliates is more than $250 million measured on the last business day of our second fiscal quarter, or our annual revenues are less than $100 million during the most recently completed fiscal year and our common stock held by non-affiliates is more than $700 million measured on the last business day of our second fiscal quarter.

**USE OF PROCEEDS**

Except as may be stated in the applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you, we intend to use the net proceeds we receive from the sale of the securities offered by this prospectus for general corporate purposes, which may include, among other things, repayment of debt, repurchases of common stock, capital expenditures, the financing of possible acquisitions or business expansions, increasing our working capital and the financing of ongoing operating expenses and overhead.

**PLAN OF DISTRIBUTION**

We may sell the securities offered by this prospectus from time to time in one or more transactions, including without limitation:

● through underwriters or dealers;

● directly to purchasers;

● in a rights offering;

● in "at the market" offerings, within the meaning of Rule 415(a)(4) of the Securities Act, to or through a market maker or into an existing trading market on an exchange or otherwise;

● through agents;

● through a combination of any of these methods; or

● through any other method permitted by applicable law and described in a prospectus supplement.

In addition, we may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with such a transaction, the third parties may sell securities covered by and pursuant to this prospectus and any accompanying prospectus supplement. If so, the third party may use securities borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and any accompanying prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and any accompanying prospectus supplement.

The prospectus supplement with respect to any offering of securities will include the following information:

● the terms of the offering;

● the names of any underwriters, dealers or direct purchasers;

● the name or names of any managing underwriter or underwriters;

● the purchase price or public offering price of the securities;

● the net proceeds from the sale of the securities;

● any delayed delivery arrangements;

● any underwriting discounts, commissions and other items constituting underwriters' compensation;

● any discounts or concessions allowed or reallowed or paid to dealers;

● any commissions paid to agents; and

● any securities exchange on which the securities may be listed.

**Sale through Underwriters or Dealers**

If underwriters are used in the sale, the underwriters will acquire the securities for their own account. The underwriters may resell the securities from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Underwriters may offer securities to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. Unless we inform you otherwise in the applicable prospectus supplement, the obligations of the underwriters to purchase the securities will be subject to certain conditions, and the underwriters will be obligated to purchase all of the offered securities if they purchase any of them. The underwriters may change from time to time any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers.

During and after an offering through underwriters, the underwriters may purchase and sell the securities in the open market. These transactions may include overallotment and stabilizing transactions and purchases to cover syndicate short positions created in connection with the offering. The underwriters may also impose a penalty bid, which means that selling concessions allowed to syndicate members or other broker-dealers for the offered securities sold for their account may be reclaimed by the syndicate if the offered securities are repurchased by the syndicate in stabilizing or covering transactions. These activities may stabilize, maintain or otherwise affect the market price of the offered securities, which may be higher than the price that might otherwise prevail in the open market. If commenced, the underwriters may discontinue these activities at any time.

Some or all of the securities that we offer through this prospectus may be new issues of securities with no established trading market. Any underwriters to whom we sell our securities for public offering and sale may make a market in those securities, but they will not be obligated to do so, and they may discontinue any market making at any time without notice. Accordingly, we cannot assure you of the liquidity of, or continued trading markets for, any securities that we offer.

If dealers are used in the sale of securities, we will sell the securities to them as principals. They may then resell those securities to the public at fixed prices or at varying prices determined by the dealers at the time of resale. We will include in the applicable prospectus supplement the names of the dealers and the terms of the transaction.

If agents are used in an offering, the names of the agents and the terms of the agency will be specified in a prospectus supplement. Unless otherwise indicated in a prospectus supplement, the agents will act on a best-efforts basis for the period of their appointment.

Dealers and agents named in a prospectus supplement may be underwriters as defined in the Securities Act and any discounts or commissions they receive from us and any profit on their resale of the securities may be treated as underwriting discounts and commissions under the Securities Act. We will identify in the applicable prospectus supplement any underwriters, dealers or agents and will describe their compensation. We may have agreements with the underwriters, dealers and agents to indemnify them against specified civil liabilities, including liabilities under the Securities Act.

Underwriters, dealers or agents and their associates may engage in other transactions with and perform other services for us in the ordinary course of business.

If so indicated in a prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by institutional investors to purchase securities pursuant to contracts providing for payment and delivery on a future date. We may enter contracts with commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutional investors. The obligations of any institutional investor will be subject to the condition that its purchase of the offered securities will not be illegal at the time of delivery. The underwriters and other agents will not be responsible for the validity or performance of contracts.

**Direct Sales and Sales through Agents**

We may sell the securities directly. In this case, no underwriters or agents would be involved. We may also sell the securities through agents designated by us from time to time. In the applicable prospectus supplement, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable to the agent. Unless we inform you otherwise in the applicable prospectus supplement, any agent will agree to use its reasonable best efforts to solicit purchases for the period of its appointment.

We may sell the securities directly to institutional investors or others who may be deemed to be underwriters within the meaning of the Securities Act with respect to any sale of those securities. We will describe the terms of any sales of these securities in the applicable prospectus supplement.

**At the Market Offerings**

We may also sell the securities offered by any applicable prospectus supplement in "at the market offerings" within the meaning of Rule 415(a)(4) of the Securities Act, to or through a market maker or into an existing trading market, on an exchange or otherwise.

**Remarketing Arrangements**

Securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreements, if any, with us and its compensation will be described in the applicable prospectus supplement.

**Delayed Delivery Contracts**

If we so indicate in the applicable prospectus supplement, we may authorize agents, underwriters or dealers to solicit offers from certain types of institutions to purchase securities from us at the public offering price under delayed delivery contracts. These contracts would provide for payment and delivery on a specified date in the future.

The contracts would be subject only to those conditions described in the applicable prospectus supplement. The applicable prospectus supplement will describe the commission payable for solicitation of those contracts.

**General Information**

We may have agreements with the underwriters, dealers, agents and remarketing firms to indemnify them against certain civil liabilities, including liabilities under the Securities Act, or to contribute with respect to payments that the underwriters, dealers, agents or remarketing firms may be required to make. Underwriters, dealers, agents and remarketing firms may be customers of, engage in transactions with or perform services for us in the ordinary course of their businesses.

**DESCRIPTION OF SECURITIES**

 ****

The following is a summary of our capital stock and certain provisions of our certificate of incorporation and bylaws. This summary does not purport to be complete and is qualified in its entirety by the provisions of our articles of incorporation, as amended, our bylaws and applicable provisions of the Delaware General Corporation Law (the "DGCL").

See "Where You Can Find More Information" elsewhere in this prospectus for information on where you can obtain copies of our articles of incorporation and our bylaws, which have been filed with and are publicly available from the SEC. Our authorized capital stock consists of 300,000,000 shares of common stock, par value $0.00001 per share, and 20,000,000 shares of preferred stock, par value $0.00001 per share.

**DESCRIPTION OF COMMON STOCK**

As of December 2, 2025, there were 58,525,488 shares of our common stock issued outstanding held by approximately 312 stockholders of record.

*Dividend Rights*

Subject to the rights of any holders of any outstanding shares or series of preferred stock, holders of common stock are entitled to the payment of dividends when and as declared by our board of directors in accordance with applicable law and to receive other distributions.

 ****

*Voting Rights*

Except as provided by law or in a preferred stock designation, holders of common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, have the exclusive right to vote for the election of directors and do not have cumulative voting rights. Except as otherwise required by law, holders of common stock are not entitled to vote on any amendment to the Certificate of Incorporation (including any certificate of designations relating to any series of preferred stock) that relates solely to the terms of any outstanding series of preferred stock if the holders of such affected series are entitled, either separately or together with the holders of one or more other such series, to vote thereon pursuant to our Certificate of Incorporation (including any certificate of designations relating to any series of preferred stock) or pursuant to the DGCL.

*Liquidation Rights*

Subject to the rights of any holders of any outstanding shares or series of preferred stock, in the event of any liquidation, dissolution or winding up of our affairs, whether voluntary or involuntary, our funds and assets, to the extent they may be legally distributed to holders of common stock, shall be distributed among the holders of the then outstanding common stock pro rata in accordance with the number of shares of common stock held by each such holder.

 ****

*Other Rights and Preferences*

All outstanding shares of common stock are fully paid and non-assessable. The holders of common stock have no pre-emptive or other subscription rights.

*Stock Exchange Listing*

Our common stock is traded on the Nasdaq Capital Market under the symbol, "ATLN."

*Transfer Agent and Registrar*

 

The transfer agent and registrar for our common stock is VStock Transfer, LLC. The address of VStock Transfer, LLC is 18 Lafayette Place, Woodmere, NY 11598 and its telephone number is (212) 828-8436.

 ****

 ****

**DESCRIPTION OF PREFERRED STOCK**

As of December 2, 2025, no shares of preferred stock had been issued or were outstanding.

The following summary of certain provisions of our preferred stock does not purport to be complete. This description is summarized from, and is qualified in its entirety by reference to, our Certificate of Incorporation and our Bylaws, to which you should refer and both of which are included as exhibits to the registration statement of which this prospectus is a part. The summary below is also qualified by provisions of applicable law, including the DGCL.

**General**

Our board of directors has the authority to issue up to 20,000,000 shares of preferred stock in one or more series and to determine the rights and preferences of the shares of any such series without stockholder approval. Our board of directors may issue preferred stock in one or more series and has the authority to fix the designation and powers, rights and preferences and the qualifications, limitations or restrictions with respect to each class or series of such class without further vote or action by the stockholders, unless action is required by applicable law or the rules of any stock exchange on which our securities may be listed. The ability of our board of directors to issue preferred stock without stockholder approval could have the effect of delaying, deferring or preventing a change of control of us or the removal of existing management. Further, our board of director 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 our common stock. Additionally, the issuance of preferred stock may have the effect of decreasing the market price of our common stock.

We will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of that series of preferred stock. This description will include, but not be limited to, the following:

● the title and stated value;

● the number of shares we are offering;

● the liquidation preference per share;

● the purchase price;

● the dividend rate, period and payment date and method of calculation for dividends;

● whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;

● the provisions for a sinking fund, if any;

● the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

● whether the preferred stock will be convertible into our common stock, and, if applicable, the conversion price, or how it will be calculated, and the conversion period;

● whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange price, or how it will be calculated, and the exchange period;

● voting rights, if any, of the preferred stock;

● preemptive rights, if any;

● restrictions on transfer, sale or other assignment, if any;

● a discussion of any material United States federal income tax considerations applicable to the preferred stock;

● the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;

● any limitations on the issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and

● any other specific terms, preferences, rights or limitations of, or restrictions on, the preferred stock.

**Transfer Agent and Registrar**

The transfer agent and registrar for our preferred stock will be set forth in the applicable prospectus supplement.

**DESCRIPTION OF DEBT SECURITIES**

**General**

We may issue debt securities, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. When we offer to sell debt securities, we will describe the specific terms of any debt securities offered from time to time in a supplement to this prospectus, which may supplement or change the terms outlined below. Senior debt securities will be issued under one or more senior indentures, dated as of a date prior to such issuance, between us and a trustee to be named in a prospectus supplement, as amended or supplemented from time to time. Any subordinated debt securities will be issued under one or more subordinated indentures, dated as of a date prior to such issuance, between us and a trustee to be named in a prospectus supplement, as amended or supplemented from time to time. The indentures will be subject to and governed by the Trust Indenture Act of 1939, as amended.

Before we issue any debt securities, the form of indentures will be filed with the SEC and incorporated by reference as an exhibit to the registration statement of which this prospectus is a part or as an exhibit to a current report on Form 8-K. For the complete terms of the debt securities, you should refer to the applicable prospectus supplement and the form of indentures for those particular debt securities. We encourage you to read the applicable prospectus supplement and the form of indenture for those particular debt securities before you purchase any of our debt securities.

We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

● the title;

● whether or not such debt securities are guaranteed;

● the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;

● any limit on the amount that may be issued;

● whether or not we will issue the series of debt securities in global form, the terms and who the depositary will be;

● the maturity date;

● the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

● whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

● the terms of the subordination of any series of subordinated debt;

● the place where payments will be payable;

● restrictions on transfer, sale or other assignment, if any;

● our right, if any, to defer payment of interest and the maximum length of any such deferral period;

● the date, if any, after which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

● the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder's option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

● any restrictions our ability and/or the ability of our subsidiaries to:

● incur additional indebtedness;

● issue additional securities;

● create liens;

● pay dividends and make distributions in respect of our capital stock and the capital stock of our subsidiaries;

● redeem capital stock;

● place restrictions on our subsidiaries' ability to pay dividends, make distributions or transfer assets;

● make investments or other restricted payments;

● sell or otherwise dispose of assets;

● enter into sale-leaseback transactions;

● engage in transactions with stockholders and affiliates;

● issue or sell stock of our subsidiaries;

● effect a consolidation or merger;

● whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

● a discussion of any material United States federal income tax considerations applicable to the debt securities;

● information describing any book-entry features;

● provisions for a sinking fund purchase or other analogous fund, if any;

● the denominations in which we will issue the series of debt securities;

● the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars; and

● any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants provided with respect to the debt securities, and any terms that may be required by us or advisable under applicable laws or regulations.

**Conversion or Exchange Rights**

We will set forth in the prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

**DESCRIPTION OF WARRANTS**

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. The terms of any warrants offered under a prospectus supplement may differ from the terms described below.

We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from reports that we file with the SEC, the form of warrant agreement, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering before the issuance of the related series of warrants. The following summaries of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectuses, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.

**General**

We will describe in the applicable prospectus supplement the terms of the series of warrants being offered, including:

● the offering price and aggregate number of warrants offered;

● the currency for which the warrants may be purchased;

● if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

● if applicable, the date on and after which the warrants and the related securities will be separately transferable;

● in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

● in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;

● the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;

● the terms of any rights to redeem or call the warrants;

● any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

● the dates on which the right to exercise the warrants will commence and expire;

● the manner in which the warrant agreements and warrants may be modified;

● a discussion of any material or special United States federal income tax consequences of holding or exercising the warrants;

● the terms of the securities issuable upon exercise of the warrants; and

● any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

● in the case of warrants to purchase debt securities, the right to receive payments of principal of, or premium, if any, or interest on, the debt securities purchasable upon exercise or to enforce covenants in the applicable indenture; or

● in the case of warrants to purchase common stock or preferred stock, the right to receive dividends, if any, or payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

**Exercise of Warrants**

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

If any warrants represented by the warrant certificate are not exercised, we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

**Outstanding Warrants**

As of the day of this prospectus, we had outstanding warrants issued by SeqLL Inc. that are exercisable to purchase an aggregate of 92,036 shares of common stock at an exercise price of $181.33 per share that expire in August 2026.

**Transfer Agent and Registrar**

The transfer agent and registrar for any warrants will be set forth in the applicable prospectus supplement.

**DESCRIPTION OF RIGHTS**

**General**

We may issue rights to purchase our common stock or preferred stock, in one or more series. Rights may be issued independently or together with any other offered security and may or may not be transferable by the person purchasing or receiving the subscription rights. In connection with any rights offering to our stockholders, we may enter into a standby underwriting arrangement with one or more underwriters pursuant to which such underwriters will purchase any offered securities remaining unsubscribed after such rights offering. In connection with a rights offering to our stockholders, we will distribute certificates evidencing the rights and a prospectus supplement to our stockholders on the record date that we set for receiving rights in such rights offering. The applicable prospectus supplement or free writing prospectus will describe the following terms of rights in respect of which this prospectus is being delivered:

● the title of such rights;

● the securities for which such rights are exercisable;

● the exercise price for such rights;

● the date of determining the security holders entitled to the rights distribution;

● the number of such rights issued to each security holder;

● the extent to which such rights are transferable;

● if applicable, a discussion of the material United States federal income tax considerations applicable to the issuance or exercise of such rights;

● the date on which the right to exercise such rights shall commence, and the date on which such rights shall expire (subject to any extension);

● the conditions to completion of the rights offering;

● any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the rights;

● the extent to which such rights include an over-subscription privilege with respect to unsubscribed securities;

● if applicable, the material terms of any standby underwriting or other purchase arrangement that we may enter into in connection with the rights offering; and

● any other terms of such rights, including terms, procedures and limitations relating to the exchange and exercise of such rights.

Each right will entitle the holder thereof the right to purchase for cash such amount of shares of common stock or preferred stock, or any combination thereof, at such exercise price as shall in each case be set forth in, or be determinable as set forth in, the prospectus supplement relating to the rights offered thereby. Rights may be exercised at any time up to the close of business on the expiration date for such rights set forth in the prospectus supplement. After the close of business on the expiration date, all unexercised rights will become void. Rights may be exercised as set forth in the prospectus supplement relating to the rights offered thereby. Upon receipt of payment and the proper completion and due execution of the rights certificate at the office of the rights agent, if any, or any other office indicated in the prospectus supplement, we will forward, as soon as practicable, the shares of common stock and/or preferred stock purchasable upon such exercise. We may determine to offer any unsubscribed offered securities directly to persons other than stockholders, to or through agents, underwriters or dealers or through a combination of such methods, including pursuant to standby underwriting arrangements, as set forth in the applicable prospectus supplement.

**Rights Agent**

The rights agent for any rights we offer will be set forth in the applicable prospectus supplement.

**DESCRIPTION OF UNITS**

The following description, together with the additional information that we include in any applicable prospectus supplement, summarizes the material terms and provisions of the units that we may offer under this prospectus. While the terms we have summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. The terms of any units offered under a prospectus supplement may differ from the terms described below.

We will incorporate by reference from reports that we file with the SEC, the form of unit agreement that describes the terms of the series of units we are offering, and any supplemental agreements, before the issuance of the related series of units. The following summaries of material terms and provisions of the units are subject to, and qualified in their entirety by reference to, all the provisions of the unit agreement and any supplemental agreements applicable to a particular series of units. We urge you to read the applicable prospectus supplements related to the particular series of units that we may offer under this prospectus, as well as any related free writing prospectuses and the complete unit agreement and any supplemental agreements that contain the terms of the units.

**General**

As specified in the applicable prospectus supplement, we may issue, in one more series, units consisting of common stock, preferred stock, debt securities and/or warrants or rights for the purchase of common stock, preferred stock and/or debt securities in any combination. The applicable prospectus supplement will describe:

● the securities comprising the units, including whether and under what circumstances the securities comprising the units may be separately traded;

● the terms and conditions applicable to the units, including a description of the terms of any applicable unit agreement governing the units; and

● a description of the provisions for the payment, settlement, transfer or exchange of the units.

The provisions described in this section, as well as those set forth in any prospectus supplement or as described under "Description of Common Stock," "Description of Preferred Stock," "Description of Debt Securities," "Description of Warrants" and "Description of Rights" will apply to each unit, as applicable, and to any common stock, preferred stock, debt security, warrant, or right included in each unit, as applicable.

**Unit Agent**

The name and address of the unit agent for any units we offer will be set forth in the applicable prospectus supplement.

**Issuance in Series**

We may issue units in such amounts and in such numerous distinct series as we may determine.

**Enforceability of Rights by Holders of Units**

Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

**DIVIDEND POLICY**

We have not declared or paid cash dividends on our capital stock to date and do not anticipate or contemplate paying dividends in the foreseeable future. We intend to retain future earnings, if any, to finance the expansion of our business, and we do not anticipate that any cash dividends will be paid in the foreseeable future. Our future payment of dividends will depend on our earnings, capital requirements, expansion plans, financial condition and other relevant factors that our board of directors may deem relevant. Our accumulated deficit currently limits our ability to pay cash dividends.

**LEGAL MATTERS**

The validity of the shares of common stock offered by this prospectus will be passed upon for us by Davidoff Hutcher & Citron LLP ("DHC"), New York, New York. DHC owns 20,000 shares of common stock of the Company.

**EXPERTS**

The financial statements of Atlantic International and its subsidiaries as of and for the years ended December 31, 2024 and 2023 incorporated by reference in this prospectus have been audited by RBSM LLP, an independent registered public accounting firm as set forth in their report, and are incorporated in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

**$250,000,000**

**Common Stock**

**Preferred Stock**

**Senior Debt Securities** 

**Subordinated Debt Securities**

**Units**

**Subscription Rights**

**Atlantic International Corp.**

**PROSPECTUS**

**__________________, 2025**

The information contained in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

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|:---|:---|:---|
| **PRELIMINARY PROSPECTUS SUPPLEMENT** | **Subject to Completion** | **Dated December 5, 2025** |

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Up to

$60,000,000

**ATLANTIC INTERNATIONAL CORP.**

$30,000,000 5% Convertible Preferred Stock

Up to ___% Warrant **coverage**

The preferred stock ("Preferred Stock") will pay a 5% annual dividend (paid-in-kind option by the Company), and will be issued with a 5% original issue discount. The Preferred Stock will be convertible at a 25% premium to the closing price of our Common Stock on the day of pricing (the "Conversion Price"). The Common Stock Purchase warrants ("Warrants") will be exercisable for five years. The Warrant Exercise Price will equal the Preferred Stock Conversion Price.

On [ ], 2025, we entered into a certain sales agreement (the "Sales Agreement"), with [\*], relating to shares of our Preferred Stock and Warrants (collectively, our "Securities") (offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, we may offer and sell shares of our Preferred Stock having an aggregate offering price of up to $30,000,000 and Warrants to purchase shares of Common Stock equal to ___% of the number of shares of Common Stock issuable upon conversion of the Preferred Stock.

Our Common Stock is listed on The Nasdaq Global Market under the symbol "ATLN." On December 4, 2025, the last reported sale price of our Common Stock on the Nasdaq Global Market was $2.28 per share.

[\*] is not required to sell any specific number or dollar amount of securities but will act as a sales agent using commercially reasonable best efforts consistent with its normal trading and sales practices, on mutually agreed terms between [\*] and us. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

The compensation to [\*] for sales of Securities sold pursuant to the sales agreement will be equal to [\*] % of the gross proceeds of any shares of Preferred Stock sold under the Sales Agreement. In connection with the sale of the Securities on our behalf, [\*] will be deemed to be an "underwriter" within the meaning of the Securities Act and the compensation of [\*] will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to [\*] with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, as amended, or the Exchange Act.

*Investing in our Securities involves a high degree of risk. See "Risk Factors" beginning on page S-4 of this prospectus supplement, and under similar headings in the other documents that are incorporated by reference into this prospectus that should be considered in connection with an investment in our Common Stock.*

**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 supplement is [_______________], 2025

**TABLE OF CONTENTS**

**Prospectus Supplement**

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|  | **Page No.** |
| [ABOUT THIS PROSPECTUS SUPPLEMENT](#s_001) | S-ii |
| [CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS](#s_002) | S-iii |
| [WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE](#s_003) | S-iv |
| [PROSPECTUS SUPPLEMENT SUMMARY](#s_004) | S-1 |
| [RISK FACTORS](#s_005) | S-4 |
| [USE OF PROCEEDS](#s_006) | S-6 |
| [MARKET PRICE OF OUR COMMON STOCK](#s_007) | S-6 |
| [DILUTION](#s_008) | S-7 |
| [DIVIDEND POLICY](#s_009) | S-7 |
| [DESCRIPTION OF SECURITIES OFFERED HEREBY](#s_010) | S-8 |
| [PLAN OF DISTRIBUTION](#s_011) | S-10 |
| [DISCLOSURE OF COMMISSION POSITION ON INDEMNIFICATION FOR SECURITIES ACT LIABILITIES.](#s_012) | S-11 |
| [LEGAL MATTERS](#s_013) | S-11 |
| [EXPERTS](#s_014) | S-11 |
| [ADDITIONAL INFORMATION](#s_015) | S-11 |

---

S-i

**ABOUT THIS PROSPECTUS SUPPLEMENT**

This prospectus supplement and the accompanying base prospectus are part of a registration statement on Form S-3 (File No. 333-__________) that we filed with the Securities and Exchange Commission (the "SEC") utilizing a "shelf" registration process. Before buying any of the Securities that we are offering, we urge you to carefully read this prospectus supplement, together with the accompanying base prospectus and the information incorporated by reference as described under the headings "Where You Can Find More Information" and "Incorporation of Certain Information by Reference" in this prospectus supplement, and any free writing prospectus that we have authorized for use in connection with this offering. Generally, when we refer only to the "prospectus," we are referring to the base prospectus and prospectus supplement combined. This prospectus supplement may add to, update or change information in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement or the accompanying prospectus. By using a "shelf" registration statement, we may offer Preferred Stock having an aggregate offering price of $30,000,000 and [\*] % Warrant coverage under this prospectus supplement at a price of $___ per share of Preferred Stock, equal to 25% premium to the closing price of our Common Stock on the date of Pricing. These documents contain important information that you should consider when making your investment decision.

This prospectus supplement describes the terms of this offering of Securities and also adds to and updates information contained in the documents incorporated by reference into this prospectus supplement. To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in any document incorporated by reference into this prospectus supplement that was filed with the SEC, before the date of this prospectus supplement, on the other hand, you should rely on the information in this prospectus supplement. 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 into this prospectus supplement — the statement in the document having the later date modifies or supersedes the earlier statement.

You should rely only on this prospectus supplement, the accompanying prospectus, the documents incorporated or deemed to be incorporated by reference herein or therein, and any free writing prospectus prepared by us or on our behalf. We have not, and the sales agent has not, authorized anyone to provide you with information different than that contained or incorporated by reference in this prospectus supplement and any free writing prospectus that we have authorized for use in connection with this offering. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. You should assume that the information appearing in this prospectus supplement, the documents incorporated by reference herein, and in any free writing prospectus that we have authorized for use in connection with this offering is accurate only as of the date of those respective documents. Our business, financial condition, results of operations and prospects may have changed since those dates. You should read this prospectus supplement, the documents incorporated by reference herein, and any free writing prospectus that we have authorized for use in connection with this offering in their entirety before making an investment decision.

We are offering to sell, and are seeking offers to buy, the shares only in jurisdictions where such offers and sales are permitted. The distribution of this prospectus and the offering of the shares in certain jurisdictions or to certain persons within such jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about and observe any restrictions relating to the offering of the shares and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference in this prospectus supplement or the accompanying prospectus were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of affairs.

Unless otherwise indicated in this prospectus supplement or the context otherwise required, all references to "we," "us," "our," "the Company," "Atlantic" and "Atlantic International Corp." refer to Atlantic International Corp. and its subsidiaries.

We own or have rights to various trademarks, service marks and trade names that we use in connection with the operation of our business. This prospectus may also contain trademarks, service marks and trade names of third parties, which are the property of their respective owners. Our use or display of third parties' trademarks, service marks, trade names or products in this prospectus is not intended to, and does not imply a relationship with, or endorsement or sponsorship by us. Solely for convenience, the trademarks, service marks and trade names referred to in this prospectus may appear without the <sup>®</sup>, <sup>TM</sup> or <sup>SM</sup> symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the right of the applicable licensor to these trademarks, service marks and trade names.

S-ii

**CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS**

This prospectus supplement, including the documents that we incorporate by reference, contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Such forward-looking statements include those that express plans, anticipation, intent, contingency, goals, targets or future development and/or otherwise are not statements of historical fact.

These forward-looking statements are based on our current expectations and projections about future events and they are subject to risks and uncertainties known and unknown to us that could cause actual results and developments to differ materially from those expressed or implied in such statements, including the risks described under "Risk Factors" in this prospectus supplement and our Annual Report on Form 10-K for the year ended December 31, 2024 as updated by our subsequent filings under the Exchange Act, each of which is incorporated by reference in this prospectus supplement in their entirety.

In some cases, you can identify forward-looking statements by terminology, such as "expects," "anticipates," "intends," "estimates," "plans," "believes," "seeks," "may," "should," "would," "could," "predicts," "future" or the negative of such terms or other similar expressions. Accordingly, these statements involve estimates, assumptions and uncertainties that could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus supplement.

You should read this prospectus supplement and the documents that we reference herein and therein, completely and with the understanding that our actual future results may be materially different from what we expect. You should assume that the information appearing in this prospectus supplement and the documents incorporated by reference is accurate as of their respective dates. Our business, financial condition, results of operations and prospects may change. We may not update these forward-looking statements, even though our situation may change in the future, unless required by law to update and disclose material developments related to previously disclosed information. We qualify all of the information presented in this prospectus supplement, and particularly our forward-looking statements, by these cautionary statements.

S-iii

**WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE**

This prospectus supplement is part of the registration statement on Form S-3 we filed with the Securities and Exchange Commission, or SEC, under the Securities Act, and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus supplement to any of our contracts, agreements or other documents, the reference may not be complete, and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. You may inspect a copy of the registration statement, including the exhibits and schedules, without charge, at the SEC's public reference room mentioned below, or obtain a copy from the SEC upon payment of the fees prescribed by the SEC.

We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read, without charge, and copy the documents we file at the SEC's public reference rooms in Washington, D.C. at 100 F Street, NE, Room 1580, Washington, DC 20549. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for further information on the public reference rooms. Our SEC filings are also available to the public at no cost from the SEC's website at http://www.sec.gov.

This prospectus supplement incorporates by reference the documents set forth below that have previously been filed with the SEC since the end of the fiscal year ended December 31, 2024:

&nbsp;&nbsp;&nbsp;&nbsp;(1) Atlantic
International [Schedule 14A](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000041/atln-20250916.htm) Proxy Statement filed with the SEC on September 17, 2025, as amended;

&nbsp;&nbsp;&nbsp;&nbsp;(2) Atlantic
International Annual Report on [Form 10-K](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000006/altn-20241231.htm) filed with the SEC on March 28, 2025;

&nbsp;&nbsp;&nbsp;&nbsp;(3) Atlantic
Quarterly Reports on Form 10-Q for the quarters ended [March 31, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000019/altn-20250331.htm) , [June 30, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000031/altn-20250630.htm) , and [September 30, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000055/altn-20250930.htm) filed with the SEC on May
14, 2025, August 14, 2025 and November 14, 2025, respectively;

&nbsp;&nbsp;&nbsp;&nbsp;(4) Current
reports on Form 8-K filed with the SEC on [January 13, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000121390025003018/ea0227522-8k_atlantic.htm) , [February 28, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000121390025018768/ea0232636-8k_atlantic.htm) , [May 5, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000010/altn-20250429.htm) , [August 11, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000027/altn-20250602.htm) , [October 31, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000043/altn-20251031.htm) and [November 10, 2025](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000050/altn-20251107.htm) , respectively; and

&nbsp;&nbsp;&nbsp;&nbsp;(5) The
descriptions of Atlantic International's common stock which is registered under Section 12 of the Exchange Act, in Atlantic International's
registration statement on [Form S-1](https://www.sec.gov/Archives/edgar/data/1605888/000121390024058504/ea0208755-s1_atlantic.htm) (No. 333-280653), filed on July 2, 2024, including any amendments or reports filed for the purpose
of updating such description.

We also incorporate by reference into this prospectus supplement additional documents (other than current reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits on such form that are related to such items) that we may file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the completion or termination of the offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information deemed furnished and not filed with the SEC. Any statements contained in a previously filed document incorporated by reference into this prospectus supplement is deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement, or in a subsequently filed document also incorporated by reference herein, modifies or supersedes that statement.

This prospectus supplement may contain information that updates, modifies or is contrary to information in one or more of the documents incorporated by reference in this prospectus. You should rely only on the information incorporated by reference or provided in this prospectus supplement. We have not authorized anyone else to provide you with different information. You should not assume that the information in this prospectus supplement is accurate as of any date other than the date of this prospectus supplement, or the date of the documents incorporated by reference in this prospectus supplement.

We will provide to each person, including any beneficial owner, to whom this prospectus supplement is delivered, upon written or oral request, at no cost to the requester, a copy of any and all of the information that is incorporated by reference in this prospectus.

You may request, and we will provide you with, a copy of these filings, at no cost, by contacting us at:

Atlantic International Corp.

270 Sylvan Avenue, Suite 2230

Englewood Cliffs, NJ

Attention: Corporate Secretary

Telephone: (201) 899-4470

S-iv

**PROSPECTUS SUPPLEMENT SUMMARY**

*The following summary is qualified in its entirety by, and should be read together with, the more detailed information and financial statements and related notes thereto appearing elsewhere or incorporated by reference in this prospectus. Before you decide to invest in our securities, you should read the entire prospectus carefully, including the risk factors and the financial statements and related notes included or incorporated by reference in this prospectus.*

*In this prospectus supplement, unless otherwise noted, the terms "the Company," "Atlantic," "we," "us," and "our" refer to Atlantic International Corp*.

**Overview**

Atlantic International Corp. (Nasdaq: ATLN), ("us", "we", the "Group", or the "Company"), through its subsidiaries, is a national strategic staffing firm servicing the commercial, professional, finance, direct placement, and managed service provider verticals, Since its formation, the Company has grown from a regional operation to a national staffing firm with offices and geographic reach across the United States. The Company primarily places individuals in accounting and finance, administrative and clerical, information technology, legal, light industrial, and medical roles. The Company is also a leading provider of productivity consulting and workforce management solutions.

We were incorporated in Delaware under the name SeqLL Inc. on April 1, 2014. On June 13, 2024, the Company changed its name from SeqLL Inc. to Atlantic International Corp. On June 4, 2024 the Company, SeqLL Merger LLC, a Delaware limited liability company and wholly-owned subsidiary of the Company ("Purchaser Sub"), Atlantic Acquisition Corp, a Delaware corporation ("Atlantic Acquisition"), Atlantic Merger LLC, a Delaware limited liability company and a majority-owned subsidiary of Atlantic Acquisition ("Atlantic Merger Sub"), Lyneer Investments, LLC, a Delaware limited liability company ("Lyneer"), and IDC Technologies, a California corporation ("IDC"), entered into the Merger Agreement pursuant to which (i) Atlantic Merger Sub was merged with and into Lyneer, with Lyneer continuing as the surviving entity and (ii) Purchaser Sub was merged with and into Lyneer with Lyneer continuing as the surviving entity and as a wholly-owned subsidiary of the Company, collectively by referred to as the Merger.

Our corporate headquarters are located at 270 Sylvan Avenue, Suite 2230, Englewood Cliffs, New Jersey 07632. Our main telephone number at that address is (201) 899-4470, and our website address is *www.atlantic-international.com*. The information on our website is not part of this prospectus. We have included our website address as a factual reference and do not intend it to be an active link to our website.

**Implications of Being an Emerging Growth Company and a Smaller Reporting Company**

We qualify as an "emerging growth company" as defined in the Jumpstart Our Business Startups Act of 2012, as amended, or the JOBS Act. As an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies.

These provisions include:

● being permitted to only disclose two years of audited financial statements in addition to any required unaudited interim financial statements with correspondingly reduced "Management's Discussion and Analysis of Financial Condition and Results of Operations" disclosure;

● reduced disclosure about our executive compensation arrangements;

● not being required to hold advisory votes on executive compensation or to obtain stockholder approval of any golden parachute arrangements not previously approved; and

● an exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting.

We may take advantage of these exemptions until the end of the fiscal year following the fifth anniversary of our initial public offering or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company on the date that is the earliest of (i) the last day of the fiscal year in which we have total annual gross revenue of $1.235 billion or more; (ii) December 31, 2025; (iii) the date on which we have issued more than $1.0 billion in nonconvertible debt during the previous three years; or (iv) the last day of the fiscal year in which we are deemed to be a large accelerated filer under the rules of the SEC, which means the market value of our Common Stock that is held by non-affiliates exceeds $700 million as of the prior June 30th. We may choose to take advantage of some but not all of these exemptions. We have taken advantage of reduced reporting requirements in this prospectus supplement. Accordingly, the information contained herein may be different from the information you receive from other public companies in which you hold stock.

We are also a "smaller reporting company" as defined in the Exchange Act. We may continue to be a smaller reporting company even after we are no longer an emerging growth company. We may take advantage of certain of the scaled disclosures available to smaller reporting companies until the fiscal year following the determination that our Common Stock held by non-affiliates is more than $250 million measured on the last business day of our second fiscal quarter, or our annual revenues are less than $100 million during the most recently completed fiscal year and our Common Stock held by non-affiliates is more than $700 million measured on the last business day of our second fiscal quarter.

**Recent Developments**

No material changes in the Company's affairs have occurred since December 31, 2024, which have not been described in a report on Form 10-Q or Form 8-K filed pursuant to the applicable provisions of the Exchange Act.

**The Offering**

---

| | |
|:---|:---|
| *Common stock outstanding prior to offering**<sup>1</sup>**:* | As of December 2, 2025, we had 58,525,488 shares of Common Stock issued and outstanding. |
| *Shares of Preferred Stock offered:* | $30,000,000 principal amount of 5% Convertible Preferred Stock. |
| Dividend | 5% (paid-in-kind by the Company) |
| Conversion Price | 25% premium to the Closing price of Common Stock on day of pricing |
| Original Issue Discount | Five (5) percent |
| Maturity | Perpetual Preferred Stock |
| Warrant Coverage | __________% of the number of shares issuable upon Conversion of Preferred Stock |
| Warrant Exercise Price | equal to the Preferred Stock conversion price. |
| *Capital Stock:* | Our authorized share capital is 300,000,000 shares of Common Stock, par value $0.00001 per share and 20,000,000 shares of preferred stock, par value $0.00001 per share. For more information about our Preferred Stock, you should carefully read the section below titled "*Description of the Securities Offered Hereby.*" |
| *Use of proceeds:* | We intend to use the net proceeds of the offering for potential acquisitions, working capital and general corporate purposes. |
| *Risk Factors:* | Investing in our Securities involves significant risks. See "*Risk Factors*" beginning on page S-4 of this prospectus supplement and other information included or incorporated by reference into this prospectus for a discussion of factors you should carefully consider before investing in our securities. |
| *Nasdaq Global Market trading symbol:* | Our shares of Common Stock are quoted on the NASDAQ Global Market under the symbol "ATLN." |

---

<sup>1</sup> Does not include:

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of 5,211,757 shares of Common Stock issuable
upon the vesting of restricted stock units ("RSUs") outstanding;

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of 1,000,000 shares of Common Stock issuable
upon exercise of Common Stock options outstanding;

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of ten (10) million shares of Common Stock initially
issuable for issuance under the 2025 Equity Incentive Plan. Of this amount, an aggregate of 4,727,887 RSUs, and 1,000,000 options are
outstanding. The number of shares of Common Stock reserved for issuance under the Incentive Plan shall be adjusted upward to reflect
fifteen (15%) percent of the number of shares issued and outstanding as of December 31<sup>st</sup> of each year.

&nbsp;&nbsp;&nbsp;&nbsp;· Up to 92,036 shares of Common Stock issuable under outstanding
Common Stock Warrants issued by SeqLL Inc. at an exercise price of $181.33 per share and expiring in August 2026.

**RISK FACTORS**

*Investing in our Securities involves a high degree of risk. Prior to making a decision about investing in our Securities, you should carefully consider the specific risk factors discussed in the sections entitled "Risk Factors" contained in our annual report on Form 10-K for the fiscal year ended December 31, 2024 under the heading "Item 1A. Risk Factors," and as described or may be described in any subsequent quarterly report on Form 10-Q under the heading "Part II, Item 1A. Risk Factors," as well as in any current reports on Form 8-K and the applicable prospectus supplement and contained or to be contained in our filings with the SEC and incorporated by reference in this prospectus, together with all of the other information contained in this prospectus, or any applicable prospectus supplement. For a description of these reports and documents, and information about where you can find them, see "Where You Can Find More Information" and "Incorporation of Certain Information by Reference." If any of the risks or uncertainties described in our SEC filings or any prospectus supplement or any additional risks and uncertainties actually occur, our business, financial condition and results of operations could be materially and adversely affected.*

**Risks Relating to this Offering**

*We may allocate the net proceeds from this offering in ways that you or other stockholders may not approve.*

We currently intend to use the net proceeds of this offering, if any, for potential acquisitions, working capital and general corporate purposes. This expected use of the net proceeds from this offering represents our intentions based upon our current plans and business conditions. However, Company's management has broad discretion as to the use of proceeds of this offering. The amounts and timing of our actual expenditures may vary significantly depending on numerous factors or assets that we may opportunistically identify and any unforeseen cash needs. Because the number and variability of factors that will determine our use of the proceeds from this offering, their ultimate use may vary substantially from their currently intended use. As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering and could spend the proceeds in ways that do not necessarily improve our operating results or enhance the value of our Preferred Stock. See "Use of Proceeds."

*You may experience future dilution as a result of future equity offerings.*

In order to raise additional capital, we may in the future offer additional shares of Common Stock or other securities convertible into or exchangeable for our Common Stock at prices that may not be the same as the Conversion Price in this offering. We may sell shares of Common Stock or Preferred Stock or other securities in any other offering at a price per share of Common Stock that is less than the Conversion Price paid by investors in this offering, and investors purchasing shares of Common Stock or other securities in the future could have rights superior to existing shareholders. The price per share of Common Stock at which we sell additional shares of Common Stock or securities convertible or exchangeable into shares of Common Stock, in future transactions may be higher or lower than the price per share of Preferred Stock paid by investors in this offering.

*We have not paid cash dividends in the past and have no immediate plans to pay dividends.*

We plan to reinvest all of our earnings, to the extent we have earnings, in order to implement our business objectives and to cover operating costs and to otherwise become and remain competitive. We do not plan to pay any cash dividends with respect to our securities in the foreseeable future. We cannot assure you that we would, at any time, generate sufficient surplus cash that would be available for distribution to the holders of our Preferred Stock as a dividend.

*Our stock price may change significantly following this offering, and stockholders may not be able to resell shares of our Common Stock at or above the price paid or at all and could lose all or part of their investment as a result.*

Stockholders may not be able to resell their shares at or above the offering price due to a number of factors such as the following:

&nbsp;&nbsp;&nbsp;&nbsp;▪ results of operations that vary from the expectations of
securities analysts and investors;

&nbsp;&nbsp;&nbsp;&nbsp;▪ results of operations that vary from those of our competitors
compared to market expectations;

&nbsp;&nbsp;&nbsp;&nbsp;▪ changes in expectations as to our future financial performance,
including financial estimates and investment recommendations by securities analysts and investors;

&nbsp;&nbsp;&nbsp;&nbsp;▪ changes in market valuations of, or earnings and other announcements
by, companies in our industry;

&nbsp;&nbsp;&nbsp;&nbsp;▪ declines in the market prices of stocks generally, particularly
those of pharmaceutical companies;

&nbsp;&nbsp;&nbsp;&nbsp;▪ departures of key management personnel;

&nbsp;&nbsp;&nbsp;&nbsp;▪ strategic actions by us or our competitors;

&nbsp;&nbsp;&nbsp;&nbsp;▪ announcements by us, our competitors or our vendors of significant
contracts, price reductions, new products or technologies, acquisitions, joint marketing relationships, joint ventures, other strategic
relationships or capital commitments;

&nbsp;&nbsp;&nbsp;&nbsp;▪ changes in preference of our customers;

&nbsp;&nbsp;&nbsp;&nbsp;▪ changes in general economic or market conditions or trends
in our industry or the economy as a whole and, in particular, in the consumer spending environment;

&nbsp;&nbsp;&nbsp;&nbsp;▪ changes in business or regulatory conditions which adversely
affect our industry or us;

&nbsp;&nbsp;&nbsp;&nbsp;▪ other events or factors, including those resulting from informational
technology system failures and disruptions, natural disasters, war, acts of terrorism or responses to these events.

Furthermore, the stock market may experience extreme volatility that, in some cases, may be unrelated or disproportionate to the operating performance of particular companies. These broad market and industry fluctuations may adversely affect the market price of our Common Stock, regardless of our actual operating performance. In addition, price volatility may be greater if the public float and trading volume of our Common Stock is low.

In the past, following periods of market volatility, stockholders have instituted securities class action litigation. If we were to become involved in securities litigation, it could have a substantial cost and divert resources and the attention of executive management from our business regardless of the outcome of such litigation.

**USE OF PROCEEDS**

The amount of proceeds from this offering will depend upon the number of shares of our Common Stock sold and the market price at which they are sold. Because there is no minimum offering amount required as a condition of this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time. We currently intend to use the net proceeds from this offering, if any, for potential acquisitions, working capital and general corporate purposes.

The timing and amount of our actual expenditures will be based on many factors, including cash flows from operations and the anticipated growth of our business. As of the date of this prospectus supplement, we cannot specify with certainty all of the particular uses for the net proceeds to us from this offering. As a result, our management will have broad discretion regarding the timing and application of the net proceeds from this offering. Investors will be relying on the judgment of our management regarding the application of the proceeds of this offering. Pending their ultimate use, we intend to invest the net proceeds in short-term, investment-grade, interest-bearing instruments.

**MARKET PRICE OF OUR COMMON STOCK**

Our Common Stock is presently listed on the NASDAQ Global Market under the symbol "ATLN". On December 4, 2025, the last reported sale price of our Common Stock was $2.28 per share.

**Holders of Common Stock**

As of December 2, 2025, we had 58,525,488 shares of Common Stock issued and outstanding and no shares of Preferred Stock outstanding. We had 312 registered holders of record of our Common Stock. A substantially greater number of holders of our Common Stock are "street name" or beneficial holders, whose shares of record are held through banks, brokers, other financial institutions and registered clearing agencies.

**DILUTION**

If you purchase any of the Preferred Stock offered by this prospectus supplement, you will experience dilution to the extent of the difference between the Conversion Price per share of Preferred Stock you pay in this offering and the net tangible book value per share of Common Stock immediately after this offering. Our net tangible book value (deficit) as of September 30, 2025 was ($49,865,554), or ($0.895) per share of Common Stock based on 55,713,259 shares used and outstanding. Net tangible book value (deficit) per share represents our total tangible assets of $82,456,211 (which excludes goodwill and other intangible assets), less our total liabilities of $132,321,765, divided by the aggregate number of our shares of Common Stock outstanding as of September 30, 2025.

After giving effect to the sale of our shares of Preferred Stock in the aggregate amount of $30,000,000 million at an assumed offering price of $[●] per share of Preferred Stock, and after deducting estimated offering commissions and other estimated offering expenses payable by us, our as adjusted net tangible book value as of September 30, 2025 would have been $[●], or approximately $[●] per share of Common Stock based on an aggregate of [●] shares of Common Stock issued and outstanding. This amount represents an immediate increase in net tangible book value of $[●] per share of Common Stock to existing stockholders as a result of this offering and immediate dilution of approximately $[●] per share of Common Stock to new investors purchasing our Preferred Stock in this offering. The following table illustrates this dilution on a per share basis. The as adjusted information below is illustrative only and will adjust based on the actual price to the public, the actual number of shares sold and other terms of the offering determined at the time our Preferred Stock is sold pursuant to this prospectus supplement.

---

| | |
|:---|:---|
| Assumed Offering price per share | $[●] |
| Net tangible book value per share as of September 30, 2025 | $(0.895) |
| Increase in net tangible book value per share attributable to the offering | $— |
| As-adjusted net tangible book value per share after giving effect to the offering | $[●] |
| Dilution in net tangible book value per share to new investors | $[●] |

---

In the event the offering is made at an assumed price of $[●] per share, our net tangible book value on September 30, 2025 would have been approximately $[●] per share based on an aggregate of [●] shares of Common Stock with dilution of $[●] per share to new investors.

The table above assumes for illustrative purposes that an aggregate of [●] shares of our PREFERRED Stock are sold pursuant to this prospectus supplement at a price of $[●] per share, for aggregate gross proceeds of $30,000,000. The shares sold in this offering, if any, will be sold from time to time at various prices. An increase of $1.00 per share in the price at which the shares are sold from the assumed offering price to $[●] per share assuming all of our Common Stock in the aggregate amount of $[●] are sold at that price, would result in an as adjusted net tangible book value per share after the offering of $[●] per share and would increase the dilution in net tangible book value per share to investors in this offering to [●] per share, after deducting sales agent commissions and estimated aggregate offering expenses payable by us. A decrease of $1.00 per shares in the price at which the shares are sold from the assumed offering price to [●] per share, would result in an as adjusted net tangible book value per share after the offering of [●] per share and would decrease the dilution in net tangible book value per share to investors n this offering to [●] per share, after deducting sales agent commissions and estimate aggregate offering expenses payable by us. This information is supplied for illustrative purposes only.

The per share data appearing above is based on 55,713,259 shares of outstanding as of September 30, 2025, and excludes:

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of 5,211,757 shares of Common Stock issuable
upon the vesting of restricted stock units ("RSUs") outstanding;

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of 1,000,000 shares of Common Stock issuable
upon exercise of Common Stock options outstanding;

&nbsp;&nbsp;&nbsp;&nbsp;· An aggregate of ten (10) million shares of Common Stock initially
issuable for future issue and under a 2025 Equity Incentive Plan. Of this amount an aggregate of 4,727,887 RSU's and 1,000,000
options are outstanding. The number of Shares of Common Stock reserved for issuance under the Incentive Plan shall be adjusted upward
to reflect fifteen (15%) percent of the number of shares issued and outstanding as of December 31<sup>st</sup> of each year.

&nbsp;&nbsp;&nbsp;&nbsp;· Up to 92,038 shares of Common Stock issuable under outstanding
Common Stock Warrants issued by SeqLL Inc. at an exercise price of $181.33 per share and expiring in August 2026.

**DIVIDEND POLICY**

We have not declared or paid cash dividends on our capital stock to date and do not anticipate or contemplate paying dividends in the foreseeable future. We intend to retain future earnings, if any, to finance the expansion of our business, and we do not anticipate that any cash dividends will be paid in the foreseeable future. Our future payment of dividends will depend on our earnings, capital requirements, expansion plans, financial condition and other relevant factors that our board of directors may deem relevant. Our accumulated deficit currently limits our ability to pay cash dividends.

**DESCRIPTION OF SECURITIES OFFERED HEREBY**

We are offering units consisting of one (1) share of our Preferred Stock and one (1) warrant to acquire [\*] shares of our Preferred Stock (as described below). Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each security included in the unit. The purchase agreement under which a unit is issued shall provide that the Securities included in the unit shall be issued separately.

***DESCRIPTION OF PREFERRED STOCK***

 

*This prospectus supplement sets forth certain terms of the Preferred Stock that we are offering pursuant to this prospectus supplement. This section outlines the specific legal and financial terms of the Preferred Stock. You should read this section together with the more general description of the Preferred Stock in the accompanying prospectus under the heading "Description of Preferred Stock" before investing in the Preferred Stock. In addition, this description is subject to and entirely qualified by reference to our Charter.* 

**General**

At the time of issuance, the Preferred Stock will be fully paid and non-assessable and have no preemptive, conversion or exchange rights or rights to cumulative voting. The Preferred Stock and all other preferred stock that we may issue from time to, if any, are senior as to dividends and distributions to our Common Stock. We may issue additional series of preferred stock in the future. The Original Issue Price of Preferred Stock shall be a five (5%) percent discount to the agreed upon price per share of Preferred Stock (as adjusted for any stock dividends, combinations, splits, recapitalizations and the like with respect to such shares).

**Dividends**

Holders of our Preferred Stock are entitled to receive dividends "in kind" per share in an amount equal to 5% per annum, or the dividend rate. [In addition, in the event a cash dividend or other distribution in cash is declared on shares of our Common Stock, holders of our Preferred Stock will be entitled to receive an additional amount equal to the dividend payable on the applicable number of shares of the Preferred Stock if such shares of Preferred Stock had been converted to Common Stock.

Dividends payable at the dividend rate will accrue and be cumulative. Dividends that are payable on the Preferred Stock on any Dividend Payment Date shall be payable to holders of record of the Preferred Stock as they appear on the stock register of the Company on the record date for such dividend.

Dividends on our Preferred Stock will be computed on the basis of a 360-day year consisting of twelve 30-day months.

**Voting Rights**

Except for matters provided in the Charter or Bylaws, or as otherwise required by applicable law, the holders of Preferred Stock will NOT be entitled to vote on any matter submitted to a vote of stockholders of the Company

**Conversion**

Each share of Preferred Stock shall be convertible, at the option of the holder thereof, at any time and from time to time, and without the payment of additional consideration by the holder thereof, into such number of fully paid and nonassessable shares of Common Stock of the Company at a Preferred Stock Conversion Price (as defined below) in effect at the time of conversion. The Preferred Stock Conversion Price shall initially be equal to 125% of the closing price of Common Stock on the day of pricing. Such initial Conversion Price, and the rate at which shares of Preferred Stock may be converted into shares of Common Stock, shall be subject to adjustment as provided in the Charter.

**Liquidation**

Upon any liquidation, dissolution or winding up by us, whether voluntary or involuntary, the holders of shares of our Preferred Stock will be entitled to be paid (before any distribution or payment is made upon any shares of Common Stock) the liquidation preference per share. However, if upon liquidation, the available funds and assets to be distributed among the holders of our Preferred Stock are insufficient to permit payment in full of the liquidation preference per share, then our entire available funds and assets upon liquidation shall be distributed ratably among the holders on a pro rata basis.

If there are any of our available funds or assets upon liquidation remaining after the payment or distribution to the holders of the Preferred Stock of their full preferential amounts described above, all such remaining available funds and assets shall be distributed to the holders of Common Stock. The holders of shares of Preferred Stock will not be entitled to any further participation in any distribution of assets by the Company.

**Modification**

Without the consent of any holders of the Preferred Stock, we, when authorized by resolution of the Board of Directors may amend or modify these terms of the Preferred Stock to cure any ambiguity, correct or supplement any provision herein which may be inconsistent with any other provision in the Charter, make any other provisions with respect to matters or questions arising under these terms of the Preferred Stock that are not inconsistent with the provisions in the Charter.

***DESCRIPTION OF WARRANTS***

 ****

*This prospectus supplement sets forth certain terms of the Warrants that we are offering pursuant to this prospectus supplement. This section outlines the specific legal and financial terms of the Preferred Warrants. You should read this section together with the more general description of the Warrants in the accompanying prospectus under the heading "Description of Warrants" before investing in the Warrants. In addition, this description is subject to and entirely qualified by reference to our Charter.* 

 

The warrants (the "Warrants") will be issued in the form of warrant certificates. The exercise price (the "Exercise Price") per share of Common Stock purchasable upon exercise of the Warrant will be equal to the Preferred Stock Conversion Price. The Warrants will, among other things, include provisions for the appropriate adjustment in exercise price of the Warrants and the class and number of the shares to be issued upon exercise of the Warrants upon the occurrence of certain events, including any subdivision, consolidation or reclassification of our shares, the payment of stock dividends, our amalgamation, and certain distributions.

The shares of Common Stock underlying the Warrants, when issued upon exercise of a Warrant, will be fully paid and non-assessable, and we will pay any transfer tax, transfer agent fee, or other incidental tax or expense incurred as a result of the issuance of Common Stock to the holder upon its exercise. We are not required to issue fractional shares upon the exercise of a Warrant. In lieu of any fractional share that would otherwise be issuable, we will pay the Warrant holder cash equal to the product of such fraction multiplied by the Exercise Price.

At any time before [\*], 2030 (the "Expiration Date"), a Warrant may be exercised upon delivery to us, of the exercise form found on the back of the Warrant certificate completed and executed as indicated, accompanied by payment of the exercise price in immediately available funds for the number of shares of Common Stock with respect to which the Warrant is being exercised.

The foregoing discussion of material terms and provisions of the Warrants is qualified in its entirety by reference to the detailed provisions of the Warrant certificate, which will be provided to each purchaser in this offering and will be filed as an exhibit to this Registration Statement Form S-3, of which this Prospectus Supplement forms a part.

**PLAN OF DISTRIBUTION**

We have entered into the sales agreement with [\*] under which we may issue and sell up to $30,000,000 of Convertible Preferred Stock and Warrants to or through [\*], acting as our sales agent. The below description of the material provisions of the Sales Agreement does not purport to be a complete statement of its terms and conditions. The Sales Agreement has been filed as an exhibit to the Registration Statement on Form S-3 of which this prospectus supplement forms a part.

The offering pursuant to the Sales Agreement will terminate upon the earlier of (i) the sale of all shares of Convertible Preferred Stock subject to the sales agreement and (ii) termination of the sales agreement as permitted therein. We may terminate the Sales Agreement in our sole discretion at any time by giving three days' prior notice to [\*] [\*] may terminate the sales agreement under the circumstances specified in the sales agreement and in its sole discretion at any time by giving three days' prior notice to us.

This prospectus supplement in electronic format may be made available on a website maintained by [\*], and [\*] may distribute this prospectus supplement electronically.

**Fees and Expenses**

We will pay [\*] commissions for its services in acting as our sales agent in the sale of our Convertible Preferred Stock pursuant to the Sales Agreement. [\*] will be entitled to compensation at a fixed commission rate of 3% of the gross proceeds from the sale of our Convertible Preferred Stock on our behalf pursuant to the Sales Agreement. We have also agreed to reimburse [\*] for its reasonable and documented out-of-pocket expenses (including but not limited to the reasonable and documented fees and expenses of its legal counsel) in an amount not to exceed $[\*].

We estimate that the total expenses for this offering, excluding compensation payable to [\*] and certain expenses reimbursable to [\*] under the terms of the sales agreement, will be approximately $[\*]. The remaining sales proceeds, after deducting any expenses payable by us and any transaction fees imposed by any governmental, regulatory, or self-regulatory organization in connection with the sales, will equal our net proceeds for the sale of such Convertible Preferred Stock.

**Regulation M**

In connection with the sale of the Convertible Preferred Stock on our behalf, [\*] will be deemed to be an "underwriter" within the meaning of the Securities Act, and the compensation of [\*] will be deemed to be underwriting commissions or discounts.

[\*] will not engage in any market making activities involving our Convertible Preferred Stock while the offering is ongoing under this prospectus supplement if such activity would be prohibited under Regulation M or other anti-manipulation rules under the Securities Act. As our sales agent, [\*] will not engage in any transactions that stabilizes our Convertible Preferred Stock.

**Indemnification**

We have agreed to indemnify [\*] against certain civil liabilities, including liabilities under the Securities Act and the Exchange Act, and to contribute to payments that the [\*] may be required to make in respect of such liabilities.

**Listing**

Our Common Stock is listed on the NASDAQ Global Market under the symbol "ATLN."

**Prior and Future Arrangements with [\*]**

[\*] and/or its affiliates have not provided, but may in the future provide, various investment banking and other financial services for us, for which services they have received and may in the future receive customary fees.

**DISCLOSURE OF COMMISSION POSITION ON INDEMNIFICATION FOR SECURITIES ACT LIABILITIES.**

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers or persons controlling the registrant pursuant to the foregoing provisions, the Company has been informed that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is therefore unenforceable.

**LEGAL MATTERS**

The validity of the shares of Common Stock offered by this prospectus supplement will be passed upon by the law form of Davidoff Hutcher and Citron LLP, New York, New York, which owns 20,000 shares of our Common Stock. [\*]is being represented in connection with this offering by [\*].

**EXPERTS**

The financial statements and the related financial statement schedules, incorporated in this prospectus supplement by reference from the Company's annual report on Form 10-K for the years ended December 31, 2023 and December 31, 2024, have been audited by RBSM, LLP, an independent registered public accounting firm, as stated in its reports, which are incorporated herein by reference. Such financial statements and financial statement schedule have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

**ADDITIONAL INFORMATION**

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities offered by this prospectus supplement. Pursuant to SEC rules, this prospectus supplement, which is part of the registration statement, omits certain information, exhibits, schedules and undertakings set forth in the registration statement. For further information pertaining to us and our securities, reference is made to our SEC filings and to the registration statement and the exhibits and schedules to the registration statement of which this prospectus supplement forms a part. Statements contained in this prospectus supplement as to the contents or provisions of any documents referred to in this prospectus are not necessarily complete, and in each instance where a copy of the document has been filed as an exhibit to the registration statement, reference is made to the exhibit for a more complete description of the matters involved.

In addition, registration statements and certain other filings made with the SEC electronically are publicly available through the SEC's web site at http://www.sec.gov. The registration statement, including all exhibits and amendments to the registration statement, has been filed electronically with the SEC.

We are subject to the information and periodic reporting requirements of the Exchange Act and, in accordance with such requirements, will file periodic reports, proxy statements, and other information with the SEC. These periodic reports, proxy statements, and other information will be available for inspection and copying at the web site of the SEC referred to above.

You should rely only on the information in this prospectus supplement and the additional information described above and under the heading "Incorporation of Certain Information by Reference" above. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information in this prospectus supplement was accurate on the date of the front cover of this prospectus only. Our business, financial condition, results of operations and prospects may have changed since that date.

The representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference into this prospectus supplement were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

**ATLANTIC INTERNATIONAL CORP.**

$30,000,000 Shares of 5% Convertible Preferred Stock

**UP TO _______%** WARRANT COVERAGE

**PROSPECTUS SUPPLEMENT**

**[\*]**

_______________, 2025

**PART II**

**INFORMATION NOT REQUIRED IN PROSPECTUS**

**ITEM 13. EXPENSES OF ISSUANCE AND DISTRIBUTION**

The expenses in connection with the issuance and distribution of the securities being registered, other than underwriting discounts and commissions, are estimated below:

---

| |
|:---|
| SEC registration fee |
| FINRA filing fee \* |
| Legal fees and expenses \* |
| Accounting fees and expenses \* |
| Transfer agent fees and expenses \* |
| Printing and engraving expenses \* |
| Miscellaneous expenses \* |
| Total \* |

---

\* Estimated expenses are presently not known and cannot be estimated.

**ITEM 14. INDEMNIFICATION OF DIRECTORS AND OFFICERS**

Section 102 of the General Corporation Law of the State of Delaware permits a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except for breaches of the director's duty of loyalty to the corporation or its stockholders, acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of a law, authorizations of the payments of a dividend or approval of a stock repurchase or redemption in violation of Delaware corporate law or for any transactions from which the director derived an improper personal benefit. Our certificate of incorporation will provide that no director will be liable to us or our stockholders for monetary damages for breach of fiduciary duties as a director, subject to the same exceptions as described above. We also expect to maintain standard insurance policies that provide coverage (1) to our directors and officers against loss arising from claims made by reason of breach of duty or other wrongful act and (2) to us with respect to indemnification payments we may make to such officers and directors.

Section 145 of the General Corporation Law of the State of Delaware provides that a corporation has the power to indemnify a director, officer, employee, or agent of the corporation and certain other persons serving at the request of the corporation in related capacities against expenses (including attorneys' fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by the person in connection with a threatened, pending, or completed action, suit or proceeding to which he or she is or is threatened to be made a party by reason of such position, if such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful, except that, in the case of actions brought by or in the right of the corporation, indemnification is limited to expenses (including attorneys' fees) actually and reasonably incurred by the person in connection with defense or settlement of such action or suit and no indemnification shall be made with respect to any claim, issue, or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or other adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper. In addition, to the extent that a present or former director or officer of a corporation has been successful on the merits or otherwise in defense of any action, suit, or proceeding described above (or claim, issue, or matter therein), such person shall be indemnified against expenses (including attorneys' fees) actually and reasonably incurred by such person in connection therewith. Expenses (including attorneys' fees) incurred by an officer or director in defending any civil, criminal, administrative, or investigative action, suit, or proceeding may be advanced by the corporation upon receipt of an undertaking by such person to repay such amount if it is ultimately determined that such person is not entitled to indemnification by the corporation under Section 145 of the General Corporation Law of the State of Delaware.

Our amended and restated certificate of incorporation provides that we will, to the fullest extent permitted by law, indemnify any person made or threatened to be made a party to an action or proceeding by reason of the fact that he or she (or his or her testators or intestate) is or was our director or officer or serves or served at any other corporation, partnership, joint venture, trust or other enterprise in a similar capacity or as an employee or agent at our request, including service with respect to employee benefit plans maintained or sponsored by us, against expenses (including attorneys'), judgments, fines, penalties and amounts paid in settlement incurred in connection with the investigation, preparation to defend, or defense of such action, suit, proceeding, or claim. However, we are not required to indemnify or advance expenses in connection with any action, suit, proceeding, claim, or counterclaim initiated by us or on behalf of us. Our amended and restated bylaws provide that we will indemnify and hold harmless each person who was or is a party or threatened to be made a party to any action, suit, or proceeding by reason of the fact that he or she is or was our director or officer, or is or was serving at our request in a similar capacity of another corporation, partnership, joint venture, trust or other enterprise, including service with respect to employee benefit plans (whether the basis of such action, suit, or proceeding is an action in an official capacity as a director or officer or in any other capacity while serving as a director of officer) to the fullest extent authorized by the Delaware General Corporation Law against all expense, liability and loss (including attorney's fees, judgments, fines, ERISA excise taxes, or penalties and amounts paid in settlement) reasonably incurred or suffered by such person in connection with such action, suit or proceeding, and this indemnification continues after such person has ceased to be an officer or director and inures to the benefit of such person's heirs, executors and administrators. The indemnification rights also include the right generally to be advanced expenses, subject to any undertaking required under Delaware General Corporation Law, and the right generally to recover expenses to enforce an indemnification claim or to defend specified suits with respect to advances of indemnification expenses.

**ITEM 15. RECENT SALES OF UNREGISTERED SECURITIES.**

We did not sell any securities that were not registered under the Securities Act of 1933, as amended (the "Securities Act") in the past three years.

**ITEM 16. EXHIBITS AND FINANCIAL SCHEDULES**

*(a) Exhibits:*

---

| | |
|:---|:---|
| **Exhibit No.** | **Document Description** |
| 1.1 | Form of Underwriting Agreement<sup>\*</sup> |
| 1.2 | Form of Sales Agreement by and between Atlantic International Corp. and [\*] |
| 3.1 | [Certificate of Amendment of the Third Amended and Restated Certificate of Incorporation of SeqLL Inc <sup>(1)</sup>](https://www.sec.gov/Archives/edgar/data/1605888/000121390023072292/ea184395ex3-1_seqllinc.htm) |
| 3.2 | [Amended and Restated Certificate of Incorporation of the Registrant<sup>(2)</sup>](https://www.sec.gov/Archives/edgar/data/1605888/000121390021018894/fs12021ex3-3_seqllinc.htm) |
| 3.3 | [Amended and Restated Bylaws of the Registrant<sup>(3)</sup>](https://www.sec.gov/Archives/edgar/data/1605888/000160588825000043/ex31amendedandrestatedbyla.htm) |
| 5.1 | [Opinion of Counsel to Registrant](ea026855701ex5-1_atlantic.htm) |
| 23.1 | [Consent of RBSM, LLP](ea026855701ex23-1_atlantic.htm) |
| 23.2 | [Consent of Davidoff Hutcher & Citron LLP (included in Exhibit 5.1)](ea026855701ex5-1_atlantic.htm) |
| 24.1 | [Power of Attorney (included on the signature page)](#poa) |
| 107 | [Filing Fee Table](ea026855701ex-fee_atlantic.htm) |

---

\* To be filed by Amendment to this Registration Statement.

(1) Incorporated by reference to the filing of Form 8-K by the
Registrant on August 30, 2023.

(2) Incorporated by reference to the filing of the Registration
Statement on Form S-1 (No. 333-254886) filed by the Registrant on March 31, 2021 and declared effective on August 26, 2021.

(3) Incorporated by reference to the filing of Exhibit 3.1 to
Form 8-K filed by the Registrant on October 31, 2023.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b) *Financial Statement Schedules*: All schedules are omitted because the required information is inapplicable or the information was previously presented in the financial statements and the related notes thereto.

**Item 17. UNDERTAKINGS**

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

*provided, however,* that paragraphs (a)1(i) and (a)(1)(ii) of above do not apply if the registration statement is on Form S-8, and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial *bona fide* offering thereof.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser, each prospectus filed the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. *Provided, however*, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(5) That, for the purpose of determining any liability under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424 (§ 230.424 of this chapter);

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(6) For purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(7) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

**SIGNATURES**

Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized on the 5th day of December 2025.

---

| | |
|:---|:---|
| **ATLANTIC INTERNATIONL CORP.** | **ATLANTIC INTERNATIONL CORP.** |
| By: | */s/ Jeffrey Jagid* |
| Name: | *Jeffrey Jagid* |
| Title: | Chief Executive Officer |

---

We, the undersigned officers and directors of ATLANTIC INTERNATIONAL CORP., hereby severally constitute and appoint Jefrey Jagid and Michael Tenore (with full power to each of them to act alone), our true and lawful attorneys-in-fact and agents, with full power of substitution and re-substitution, for us and in our stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement and all documents relating thereto, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them full power and authority to do and perform each and every act and thing necessary or advisable to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their substitute or substitutes, may lawfully do or cause to be done by virtue thereof.

WITNESS our hands and common seal on the dates set forth below.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| */s/ Jeffrey Jagid* |  |  |
| Jeffrey Jagid | Chief Executive Officer | December 5, 2025 |
|  | (Principal Executive Officer, Interim Principal Accounting and |  |
|  | Financial Officer, and Director) |  |
| /s/ *Robert B. Machinist* |  |  |
| Robert B. Machinist | Vice Chairman and Director | December 5, 2025 |
| */s/ Jeff Kurtz* |  |  |
| Jeff Kurtz | Director | December 5, 2025 |
| */s/ David Pfeffer* |  |  |
| David Pfeffer | Director | December 5, 2025 |
| */s/ David Solimine* |  |  |
| David Solimine | Director | December 5, 2025 |

---

## Exhibit 5.1

**Exhibit 5.1**

**DAVIDOFF HUTCHER & CITRON LLP**

605 Third Avenue

New York, New York 10158

(212) 557-7200

December 5, 2025

Atlantic International Corp.

270 Sylvan Avenue, Suite 2230,

Englewood Cliffs, New Jersey 07632

Re: <u>Registration Statement on Form S-3</u>

Ladies and Gentlemen:

We have acted as counsel for Atlantic International Corp., a Delaware corporation (the "Company"), in connection with the filing, with the Securities and Exchange Commission (the "Commission" or "SEC"), by the Company, of a Registration Statement on Form S-3 (such registration statement, as amended or supplemented, is hereinafter referred to as the "Registration Statement") filed on the date hereof under the Securities Act of 1933, as amended (the "Securities Act").

The Registration Statement relates to the proposed issuance and sale, from time to time pursuant to the Securities Act, as set forth in the Registration Statement, the prospectus contained therein (the "Base Prospectus") and one or more supplements to the Base Prospectus (each, a "Prospectus Supplement") and any free-writing prospectus(es) of the following securities of the Company (collectively, the "Securities"): (i) shares of common stock, par value $0.00001 per share (the "Common Stock") of the Company; (ii) shares of preferred stock, par value $0.00001 per share (the "Preferred Stock"), of the Company; (iii) senior or subordinated debt securities to be issued pursuant to one or more senior or subordinated indentures, as applicable, by and between the Company and a trustee to be named in a Prospectus Supplement (the "Debt Securities"); (iv) warrants to purchase Common Stock, Preferred Stock, Debt Securities or any combination thereof, in each case as may be designated by the Company at the time of an offering (the "Warrants"); (v) subscription rights to purchase Common Stock or Preferred Stock (the "Subscription Rights"); and (vi) units consisting of shares of Common Stock, Preferred Stock, Debt Securities, Warrants, or rights to purchase such shares of Common Stock, Preferred Stock, Debt Securities, Warrants, Rights or any combination of the foregoing (the "Units"). The Securities are being registered for offering and sale from time to time pursuant to Rule 415 under the Securities Act. The aggregate public offering price of the Securities being registered is $250,000,000. We are delivering this opinion pursuant to the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

In connection with this opinion, we have assumed that the Registration Statement, and any amendments thereto will have become effective, and the Securities will be sold in the manner described in the Registration Statement and the Prospectus relating thereto.

In connection with the opinions expressed herein, we have examined originals or copies, certified or otherwise identified to our satisfaction, of such documents, corporate records, certificates of public officials and other instruments as we have deemed necessary for the purposes of rendering this opinion. In our examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity with the originals of all documents submitted to us as copies, the authenticity of the originals of such documents and the legal competence of all signatories to such documents. We have also reviewed such questions of law as we have deemed necessary or appropriate.

As to matters of fact relevant to the opinion expressed herein, and as to factual matters arising in connection with our examination of corporate documents, records and other documents and writings, we relied upon certificates and other communications of corporate officers of the Company, without further investigation as to the facts set forth therein.

Based upon the foregoing, and subject to the qualifications, assumptions and limitations stated herein, we are of the opinion that:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i) The shares of Common Stock to be issued by the Company have been duly authorized for issuance and, when
issued and paid for, will be validly issued, fully paid and non-assessable shares of Common Stock of the Company;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii) The shares of Preferred Stock to be issued by the Company have been duly authorized for issuance and,
when issued and paid for, will be validly issued, fully paid and non-assessable shares of Preferred Stock of the Company;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii) The Debt Securities, when issued and sold in accordance with a duly authorized, executed and delivered indenture relating thereto
on behalf of the Company, will be valid and legally binding obligations of the Company, enforceable against the Company in accordance
with their terms;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv) The Warrants, when issued and sold in accordance with a duly authorized, executed and delivered agreement
relating thereto on behalf of the Company, will be valid and legally binding obligations of the Company, enforceable against the Company
in accordance with their terms;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(v) The Subscription Rights, upon due execution and delivery of a subscription rights agreement relating thereto
on behalf of the Company, and upon due execution and delivery of one or more certificates bearing such terms on behalf of the Company,
will constitute valid and binding obligations of the Company in accordance with their terms;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(vi) The Units, when issued and sold in accordance with a duly authorized, executed and delivered agreement
relating thereto on behalf of the Company, will constitute valid and legally binding obligations of the Company, enforceable against the
Company in accordance with their terms.

The foregoing opinion is limited in all respect to the facts as they currently exist and the General Corporation Law of the State of Delaware (including the applicable provisions of the Delaware Constitution and the reported judicial decisions interpreting these laws) and the federal laws of the United States of America, and we do not express any opinions as to the laws of any other jurisdiction. We assume no obligations to revise or supplement this opinion in the event of future changes in such laws or the interpretation thereof or such facts.

We hereby consent to the statements with respect to us under the heading "Legal Matters" in the Prospectus and to the filing of this opinion as an exhibit to the Registration Statement. In giving these consents, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations of the Commission.

---

| |
|:---|
| Very truly yours, |
| */s/ Davidoff Hutcher & Citron LLP* |
| DAVIDOFF HUTCHER & CITRON LLP |

---

EHL/ela

cc: Atlantic International Corp.

## Exhibit 23.1

**Exhibit 23.1**

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| | |
|:---|:---|
| ![](ex23-1_001.jpg) | ***Nevada Office:***<br> ****<br> 770 East Warm Springs Road<br> Suite 225<br> Las Vegas, Nevada 89119<br> 702.413.6000<br> *www.rbsmllp.com* |

---

**CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM**

We consent to the incorporation by reference in this Registration Statement of Atlantic International Corp. on Form S-3 of our report dated March 28, 2025, relating to the financial statements of Atlantic International Corp., as of December 31, 2024 and 2023, and for each of the years in the two-year period ended December 31, 2024.

We also consent to the reference to us under the heading "Experts" in the Prospectus, which is part of this Registration Statement.

/s/ RBSM LLP

Las Vegas, Nevada

December 5, 2025

## Ex-Filing

?xml version='1.0' encoding='ASCII'? Filing Fee Exhibit

**Ex-Filing Fees**

**CALCULATION OF FILING FEE TABLES**

**S-3**

**Atlantic International Corp.**

**Table 1: Newly Registered and Carry Forward Securities**

---

| | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| **Line Item Type** | **Security Type** | **Security Class Title** | **Notes** | **Fee Calculation<br> Rule** | **Amount Registered** | **Proposed Maximum Offering<br> Price Per Unit** | **Maximum Aggregate Offering Price** | **Fee Rate** | **Amount of Registration Fee** |
| *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* | *Newly Registered Securities* |
| Fees to be Paid | Equity | Common Stock, par value $0.00001 per share | (1) | 457(o) |  | $| $— | 0.0001381 | $— |
| Fees to be Paid | Equity | Preferred Stock, par value $0.00001 per share | (2) | 457(o) |  |  |  | 0.0001381 |  |
| Fees to be Paid | Debt | Debt Securities | (3) | 457(o) |  |  |  | 0.0001381 |  |
| Fees to be Paid | Other | Warrants | (4) | 457(o) |  |  |  | 0.0001381 |  |
| Fees to be Paid | Other | Subscription Rights | (5) | 457(o) |  |  |  | 0.0001381 |  |
| Fees to be Paid | Other | Units | (6) | 457(o) |  |  |  | 0.0001381 |  |
| Fees to be Paid | Unallocated (Universal) Shelf |  | (7) | 457(o) |  | $| $250000000.00 | 0.0001381 | $34525.00 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | $250000000.00 |  | 34525.00 |
| Total Fees Previously Paid: | Total Fees Previously Paid: | Total Fees Previously Paid: | Total Fees Previously Paid: | Total Fees Previously Paid: | Total Fees Previously Paid: | Total Fees Previously Paid: |  |  | 0.00 |
| Total Fee Offsets: | Total Fee Offsets: | Total Fee Offsets: | Total Fee Offsets: | Total Fee Offsets: | Total Fee Offsets: | Total Fee Offsets: |  |  | 0.00 |
| Net Fee Due: | Net Fee Due: | Net Fee Due: | Net Fee Due: | Net Fee Due: | Net Fee Due: | Net Fee Due: |  |  | $34525.00 |

---

**__________________________________________ Offering Note(s)**

&nbsp;&nbsp;&nbsp;&nbsp;(1) Including such currently indeterminate amount of Common Stock as may be issued from time to time at currently indeterminate prices or upon conversion or exchange of Debt Securities or Preferred Stock registered hereby, or upon exercise of Warrants or Subscription Rights registered hereby, as the case may be.

&nbsp;&nbsp;&nbsp;&nbsp;(2) Including such currently indeterminate amount of Preferred Stock as may be issued from time to time at currently indeterminate prices or upon exercise of Warrants or Subscription Rights registered hereby, as the case may be.

&nbsp;&nbsp;&nbsp;&nbsp;(3) Including such currently indeterminate principal amount of Debt Securities as may be issued from time to time at currently indeterminate prices or upon exercise of Warrants registered hereby, as the case may be.

&nbsp;&nbsp;&nbsp;&nbsp;(4) Including such currently indeterminate number of Warrants as may be issued from time to time at currently indeterminate prices.

&nbsp;&nbsp;&nbsp;&nbsp;(5) Including such currently indeterminate number of Subscription Rights, as may be issued from time to time at currently indeterminate prices.

&nbsp;&nbsp;&nbsp;&nbsp;(6) Including such currently indeterminate number of Units as may be issued from time to time at currently indeterminate prices. Each Unit will represent an interest in two or more securities registered hereby, which may or may not be separable from one another.

&nbsp;&nbsp;&nbsp;&nbsp;(7) There are being registered under this registration statement such indeterminate number of shares of Common Stock and Preferred Stock; such indeterminate number of Debt Securities; such indeterminate number of Warrants; such indeterminate number of Subscription Rights; and such indeterminate number of Units as may be sold by the registrant from time to time, which together shall have an aggregate initial offering price not to exceed $250,000,000. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. Includes consideration to be received by the registrant, if applicable, for registered securities that are issuable upon exercise, conversion or exchange of other registered securities. In addition, pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"), the shares being registered hereunder include such indeterminate number of shares of Common Stock and preferred stock as may be issuable with respect to the shares being registered hereunder as a result of stock splits, stock dividends, or similar transactions. The registration fee for securities to be offered by the Registrant is calculated solely for the purpose of calculating the registration fee pursuant to Rule 457(o).