# EDGAR Filing Document

**Accession Number:** 0001877939
**File Stem:** 0001213900-25-053488
**Filing Date:** 2025-6
**Character Count:** 126310
**Document Hash:** dc8e901f9f7fd9e526575b8512c031fd
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-25-053488.hdr.sgml**: 20250611

**ACCESSION NUMBER**: 0001213900-25-053488

**CONFORMED SUBMISSION TYPE**: 424B5

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250611

**DATE AS OF CHANGE**: 20250611

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Castellum, Inc.
- **CENTRAL INDEX KEY:** 0001877939
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-MANAGEMENT CONSULTING SERVICES [8742]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 274079982
- **STATE OF INCORPORATION:** NV
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 424B5
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-284205
- **FILM NUMBER:** 251040669

**BUSINESS ADDRESS:**
- **STREET 1:** 1934 OLD GALLOWS ROAD
- **STREET 2:** SUITE 350
- **CITY:** VIENNA
- **STATE:** VA
- **ZIP:** 22182
- **BUSINESS PHONE:** (703) 752-6157

**MAIL ADDRESS:**
- **STREET 1:** 1934 OLD GALLOWS ROAD
- **STREET 2:** SUITE 350
- **CITY:** VIENNA
- **STATE:** VA
- **ZIP:** 22182

**PROSPECTUS SUPPLEMENT**

**(To Prospectus dated January 24, 2025)**

**Filed Pursuant to Rule 424(b)(5)**

**Registration No. 333-284205**

**Castellum, Inc.**

**Units consisting of Shares of Common Stock and Warrants to purchase up to Shares of Common Stock** 

We are offering units (the "Units", with each Units consisting of one (1) share of common stock, par value $0.0001 per share ("Common Stock"), and one (1) warrant to purchase one share of common stock at a price of $ per share (the "Warrant"), or collectively, the "Warrants"). Each Unit is being sold at a price of $.

We do not intend to apply for listing of the Warrants on any national securities exchange or other trading market, and we do not believe any such market will develop. Therefore, the liquidity of the Warrants will be limited and should be considered illiquid. The Units have no stand-alone rights and will not be certificated or issued as stand-alone securities. The shares of common stock and the Warrants underlying the Units are immediately separable and will be issued separately in this offering. The Warrants will have an exercise price of $__ per whole share and will be exercisable from the initial issuance date until expiration.

This offering also relates to the shares of Common Stock issuable upon exercise of the Warrants sold in this offering. The shares of Common Stock can each be purchased in this offering only with the accompanying Warrants.

Our Common Stock is listed on the NYSE American LLC (the "NYSE American") under the symbol "CTM". On June 10, 2025, the last reported sale price of our Common Stock on the NYSE American was $1.39.

We have retained Maxim Group LLC, referred to herein as "Maxim" or the "placement agent", to act as our exclusive placement agent in connection with the securities offered by this prospectus supplement and the accompanying prospectus. The placement agent has no obligation to buy any of the securities from us or to arrange for the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay the placement agent the placement agent fees set forth in the table below, which assumes that we sell all of the securities we are offering. See "<u>[Plan of Distribution](#s_010)</u>" beginning on page <u>S-10</u> of this prospectus supplement for more information regarding these arrangements.

We are an "emerging growth company" and "smaller reporting company" as defined under the federal securities laws and, under applicable Securities and Exchange Commission rules, we have elected to comply with certain reduced public company reporting and disclosure requirements.

**Investing in our securities involves a high degree of risk. Before making any decision to invest in our securities, you should carefully consider the information disclosed in this this prospectus supplement and the accompanying prospectus, including the information under "<u>[Risk Factors](#s_005)</u>" beginning on page <u>S-5</u> of this prospectus supplement, as well as the information, including the risk factors contained or incorporated by reference to this prospectus supplement and the accompanying prospectus as described under the heading "Where You Can Find More Information."**

**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 AND THE ACCOMPANYING PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.**

There is no arrangement for funds to be received in escrow, trust, or similar arrangement.

---

| | | |
|:---|:---|:---|
|  | **Per Unit** | **Total** |
| Offering Price | $| $|
| Placement Agent Fees<sup>(1)</sup> | $| $|
| Proceeds, before expenses, to us | $| $|

---

(1) We have agreed: (i) to pay a cash fee to the placement agent equal to 7%
of the aggregate gross proceeds raised in this offering and 3.5% of the aggregate purchase price paid pursuant to the exercise of the
Warrants; and (ii) to reimburse certain expenses of the placement agent in connection with this offering. See "Plan of Distribution"
beginning on page S-10 of this prospectus supplement for additional information regarding compensation paid to the placement agent.

We expect that delivery of the shares of Units being offered pursuant to this prospectus supplement and the accompanying base prospectus will be made on or about June , 2025, subject to satisfaction of customary closing conditions.

**Maxim Group LLC**

The date of this prospectus supplement is June , 2025.

**TABLE OF CONTENTS**

---

| | |
|:---|:---|
|  | **Page** |
| **PROSPECTUS SUPPLEMENT** |  |
| [ABOUT THIS PROSPECTUS SUPPLEMENT](#s_001) | S-ii |
| [CAUTIONARY NOTE CONCERNING FORWARD-LOOKING STATEMENTS](#s_002) | S-iii |
| [PROSPECTUS SUPPLEMENT SUMMARY](#s_003) | S-1 |
| [THE OFFERING](#s_004) | S-4 |
| [RISK FACTORS](#s_005) | S-5 |
| [USE OF PROCEEDS](#s_006) | S-6 |
| [DIVIDEND POLICY](#s_007) | S-7 |
| [DILUTION](#s_008) | S-8 |
| [DESCRIPTION OF THE SECURITIES WE ARE OFFERING](#s_009) | S-9 |
| [PLAN OF DISTRIBUTION](#s_010) | S-10 |
| [LEGAL MATTERS](#s_011) | S-13 |
| [EXPERTS](#s_012) | S-13 |
| [WHERE YOU CAN FIND MORE INFORMATION](#s_013) | S-13 |
| [INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE](#s_014) | S-14 |

---

---

| | |
|:---|:---|
|  | **Page** |
| **PROSPECTUS: DATED JANUARY 24, 2025** |  |
| [ABOUT THIS PROSPECTUS](#a_001) | 1 |
| [WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE](#a_002) | 2 |
| [THE COMPANY](#a_003) | 4 |
| [RISK FACTORS](#a_004) | 5 |
| [SPECIAL NOTICE REGARDING FORWARD-LOOKING STATEMENTS](#a_005) | 6 |
| [USE OF PROCEEDS](#a_006) | 7 |
| [DESCRIPTION OF CAPITAL STOCK](#a_007) | 8 |
| [DESCRIPTION OF PREFERRED STOCK](#a_008) | 10 |
| [DESCRIPTION OF WARRANTS](#a_009) | 12 |
| [DESCRIPTION OF RIGHTS](#a_010) | 13 |
| [DESCRIPTION OF UNITS](#a_011) | 14 |
| [DESCRIPTION OF DEBT SECURITIES](#a_012) | 15 |
| [PLAN OF DISTRIBUTION](#a_013) | 17 |
| [LEGAL MATTERS](#a_014) | 19 |
| [EXPERTS](#a_015) | 19 |

---

**You should rely only on the information we have provided or incorporated by reference in this prospectus or in any prospectus supplement. We have not authorized anyone to provide you with information different from that contained or incorporated by reference in this prospectus or in any prospectus supplement. This prospectus and any prospectus supplement is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. You should assume that the information contained in this prospectus and in any prospectus supplement is accurate only as of their respective dates and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus or any prospective supplement or any sale of securities. The registration statement, including the exhibits and the documents incorporated herein by reference, can be read on the website of the Securities and Exchange Commission, or "SEC," or on our corporate website at <u>https://investors.castellumus.com/overview/default.aspx</u> as set forth in this prospectus under the heading "Available Information."**

 

*This prospectus supplement is not an offer to sell or a solicitation of an offer to buy securities in any jurisdiction in which such offer or solicitation is illegal.*

S-i

**ABOUT THIS PROSPECTUS SUPPLEMENT**

All references to the terms the "Company," "we," "us" or "our" in this prospectus supplement refer to Castellum, Inc., a Nevada corporation, unless the context requires otherwise.

This prospectus supplement and the accompanying base prospectus are part of a registration statement that we filed with the Securities and Exchange Commission (the "SEC") on Form S-3 (File No. 333-284205) utilizing a "shelf" registration process. Each time we conduct an offering to sell securities under the accompanying base prospectus we will provide a prospectus supplement that will contain specific information about the terms of that offering, including the price, the amount of securities being offered, and the plan of distribution. The shelf registration statement was initially filed with the SEC on January 10, 2025, and was declared effective on January 24, 2025. This prospectus supplement describes the specific details regarding this offering and may add, update or change information contained in the accompanying base prospectus. The accompanying base prospectus provides general information about us and our securities, some of which, such as the section entitled "Plan of Distribution," may not apply to this offering. This prospectus supplement and the accompanying base prospectus are an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. We are not making offers to sell or solicitations to buy our securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making that offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

If information in this prospectus supplement is inconsistent with the accompanying base prospectus or the information incorporated by reference with an earlier date, you should rely on this prospectus supplement. This prospectus supplement, together with the accompanying base prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying base prospectus, include all material information relating to this offering. You should assume that the information appearing in this prospectus supplement, the accompanying base prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying base prospectus is accurate only as of the respective dates of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates. **You should carefully read this prospectus supplement, the accompanying base prospectus and the information and documents incorporated by reference herein and therein before making an investment decision. See "Where You Can Find More Information" in this prospectus supplement and in the accompanying base prospectus.**

We have not, and the placement agent has not, authorized anyone to provide you with information that is different from that contained in this prospectus supplement, the accompanying base prospectus or in any free writing prospectus we may authorize to be delivered or made available to you. When you make a decision about whether to invest in our securities, you should not rely upon any information other than the information contained in or incorporated by reference into this prospectus supplement, the accompanying base prospectus or in any free writing prospectus that we may authorize to be delivered or made available to you. Neither the delivery of this prospectus supplement and the accompanying base prospectus nor the sale of our securities means that the information contained in this prospectus supplement, the accompanying base prospectus or any free writing prospectus is correct after the date of the respective dates of such documents.

For investors outside the United States: We have not, and the placement agent has not, taken any action that would permit this offering or possession or distribution of this prospectus supplement or the accompanying base prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons outside the United States who come into possession of this prospectus supplement or the accompanying base prospectus must inform themselves about, and observe any restrictions relating to, the offering of the securities covered hereby and the distribution of this prospectus supplement and the accompanying base prospectus outside the United States.

This prospectus supplement and the accompanying base prospectus contain summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the full text of the actual documents, some of which have been filed or will be filed with the SEC and incorporated by reference herein. See "Where You Can Find More Information" in this prospectus supplement. 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 into this prospectus supplement or the accompanying base 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 our affairs.

This prospectus supplement and the accompanying base prospectus contain and incorporate by reference certain market data and industry statistics and forecasts that are based on studies sponsored by us, independent industry publications and other publicly available information. Although we believe these sources are reliable, estimates as they relate to projections involve numerous assumptions, are subject to risks and uncertainties, and are subject to change based on various factors, including those discussed under "Risk Factors" in this prospectus supplement and the accompanying base prospectus and under similar headings in the documents incorporated by reference herein and therein. Accordingly, investors should not place undue reliance on this information.

We own or have rights to certain trademarks that we use in conjunction with the operations of our business. Each trademark, trade name, service mark or copyright of any other company appearing or incorporated by reference in this prospectus supplement belongs to its holder. Solely for convenience, trademarks, trade names, service marks and copyrights referred to in this prospectus may appear with or without the "©", "®" or "™" symbols, but the inclusion, or not, of such references are not intended to indicate, in any way, that we, or the applicable owner, will not assert, to the fullest extent possible under applicable law, our or their, as applicable, rights to these trademarks, trade names service marks or copyrights. We do not intend our use or display of other companies' trademarks, trade names, service marks or copyrights to imply a relationship with, or endorsement or sponsorship of us by, such other companies.

S-ii

**CAUTIONARY NOTE CONCERNING FORWARD-LOOKING STATEMENTS**

This prospectus and the documents incorporated by reference herein contain or may contain forward looking statements that involve risks and uncertainties. All statements other than statements of historical fact contained in this prospectus, including statements regarding future events, our future financial performance, business strategy and plans and objectives of management for future operations, are forward-looking statements. We have attempted to identify forward-looking statements by terminology including "anticipates," "believes," "can," "continue," "could," "estimates," "expects," "intends," "may," "plans," "potential," "predicts," "should," or "will," or the negative of these terms or other comparable terminology. Although we do not make forward looking statements unless we believe we have a reasonable basis for doing so, we cannot guarantee their accuracy. These statements are only predictions and involve known and unknown risks, uncertainties and other factors, including the risks outlined under "Risk Factors" or elsewhere in this prospectus, which may cause our or our industry's actual results, levels of activity, performance or achievements expressed or implied by these forward-looking statements.

Forward-looking statements should not be read as a guarantee of future performance or results, and will not necessarily be accurate indications of the times at, or by which, that performance or those results will be achieved. Forward-looking statements are based on information available at the time they are made and/or management's good faith 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 what is expressed in or suggested by the forward-looking statements.

Forward-looking statements speak only as of the date they are made. You should not put undue reliance on any forward-looking statements. Except as required by law, we assume no obligation to update forward-looking statements to reflect actual results, changes in assumptions, or changes in other factors affecting forward-looking information, except to the extent required by applicable securities laws. If we do update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

S-iii

**PROSPECTUS SUPPLEMENT SUMMARY**

 

*The following summary highlights selected information contained elsewhere in or incorporated by reference into this prospectus supplement and the accompanying prospectus. The summary may not contain all of the information that you should consider before investing in our securities. You should read the entire prospectus supplement and accompany prospectus, the registration statement of which this prospectus is a part, and the information incorporated by reference into this prospectus supplement in their entirety, including the "Risk Factors" and our financial statements and the related notes incorporated by reference into this prospectus, before purchasing our securities in this offering. See the "<u>[Risk Factors](#s_005)</u>" section of this prospectus supplement beginning on page <u>S-5</u> for a discussion of the risks involved in investing in our securities. Except as otherwise indicated herein or as the context otherwise requires, references in this prospectus supplement to the "Company," "we," "us," and "our" refer to Castellum, Inc.* 

**Corporate Summary**

Castellum, Inc. is focused on building a large, successful technology company in the areas of cybersecurity, IT, electronic warfare, information warfare, and information operations with businesses in the defense, federal civilian, and commercial markets. Services include intelligence analysis, software development, software engineering, program management, strategic and mission planning, information assurance, cybersecurity and policy support, data analytics, and model based systems engineering. These services are applicable to customers in the United States government ("USG"), financial services, healthcare, and other users of large data applications. They can be delivered to on-premises enclaves or to customers who rely upon cloud-based infrastructures. The Company has worked with multiple business brokers and contacts within their business network to identify potential acquisitions. Due to our success in completing seven acquisitions over the previous five years and given our executive officers' and key managers' networks of contacts in the IT, telecom, cybersecurity, and defense sectors, we believe that we are well positioned to continue to execute our business strategy given a pipeline of identified and acquisition targets. Because of our executive officers' and key managers' prior experience growing businesses organically, we believe that we are well positioned to grow our existing business via internal growth as well. The Company has developed a qualified business opportunity (the "Opportunity Pipeline"). Although there can be no assurance that the Opportunity Pipeline can be converted to revenues, the Company believes that the total value of the Opportunity Pipeline was approximately $662 million as of March 31, 2025. The Opportunity Pipeline represents the revenue opportunity for the Company from potential future contracts obtained through organic growth from qualified customers based on the expected base year contract value plus the value of all option periods.

We provide expertise and technology to enterprise and mission customers in support of national security missions and government modernization/transformation. Due to the nature of the work being executed for the USG the budgets are expected to continue to grow in support of bipartisan national security imperatives. The majority of contracted work is operational in nature and is funded on an on-going basis.

As a government contractor, Castellum both cooperates (as a teaming partner) and competes with many different companies. Sometimes, Castellum both teams with (on one contract) and competes against (on a different contract) the same company. Among others, Castellum competes with (and sometimes also teams with) Northrup Grumman, CACI, Peraton, and Booz-Allen Hamilton.

**Corporate Information**

The Company was incorporated in Nevada on September 30, 2010 under the name Passionate Pet, Inc. and in January 2013, the Company changed its name to Firstin Wireless Technology, Inc. In March 2015, the Company changed its name to BioNovelus, Inc. On June 12, 2019, the Company acquired Bayberry Acquisition Corporation, a Nevada corporation ("Bayberry" and, as context requires, the "Bayberry Acquisition"). On February 23, 2021, Bayberry was dissolved with the Nevada Secretary of State as it was non-operational after the merger with the Company. On November 21, 2019, we acquired Corvus Consulting, LLC, ("Corvus"), originally a Virginia limited liability company. On December 26, 2019, following our acquisition of Corvus, we changed our name from BioNovelus, Inc. to Castellum, Inc.

Our principal executive offices are located at 1934 Old Gallows Road, Suite 350, Vienna, VA 22182. Our telephone number is (703) 752-6157 and our website address is www.castellumus.com. The information contained on, or accessible through, our website will not be deemed to be incorporated by reference into this prospectus and does not constitute part of this prospectus.

**Recent Developments**

On April 10, 2025, the Company issued a press release alerting holders of certain warrants of the deadline to exercise and announced that 1,145,000 warrants had been exercised.

On April 15, 2025, the Company issued a press release announcing its subsidiary, Global Technology and Management Resources, Inc. has added Special Item Number 541611 to their existing General Services Administration Multiple Aware Schedule contract.

On April 17, 2025, the Company entered into an amendment to the letter agreement dated February 24, 2024 with Robert Eisiminger (the "Amended Letter Agreement") pursuant to which Mr. Eisiminger agreed to accept a $2 million principal payment (the "Principal Payment") from the Company on two notes payable. As a result of the Principal Payment, the principal balance on the note payable with a principal balance of $400,000 dated February 28, 2022 was reduced to zero, and the principal balance of the $5,600,000 noted owed to Mr. Eisiminger dated August 2021 (the "Eisiminger Note") was reduced to $4.0 million. The parties also agreed to extend the maturity date from August 31, 2026 to December 15, 2027 on the Eisiminger Note, and increase the per annum interest rate from 8.0% to 10.0%. All other terms of the Eisiminger Note remain unchanged.

On May 28, 2025, the Company held its annual meeting of stockholders and reported the results of the meeting.

On June 2, 2025, the Company issued a press release announcing the Company will participate in the "2025 Virtual Tech Conference: Discover the Innovations Reshaping tomorrow."

On June 5, 2025, the Company issued a press release announcing the early retirement of its note payable with the Buckhout Charitable Remainder Trust.

**Implications of Being An Emerging Growth Company** 

We are an "emerging growth company" as defined in the Jumpstart Our Business Startups Act of 2012, as amended (the "JOBS Act"). An emerging growth company may take advantage of specified exemptions from various requirements that are otherwise applicable generally to public companies in the United States. These provisions include:

● presenting only 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 in this prospectus;

● reduced disclosure about our executive compensation arrangements;

● an exemption from the requirements to hold non-binding advisory votes on executive compensation and golden parachute payments;

● an exemption from the auditor attestation requirement in the assessment of the emerging growth company's internal control over financial reporting; and

● an exemption from compliance with any requirement that the Public Company Accounting Oversight Board may adopt regarding mandatory audit firm rotation or a supplement to the auditor's report providing additional information about the audit and the financial statements.

We will remain an emerging growth company until the earliest to occur of:

● the last day of the fiscal year in which we have annual gross revenues of $1.07 billion or more;

● the date on which we have issued more than $1.0 billion in non-convertible debt in the previous three years;

● the last day of the fiscal year in which we are deemed to be a "large accelerated filer" under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), which would occur if the market value of our common stock that is held by non-affiliates is $700.0 million or more as of the last business day of the second fiscal quarter of such year; and

● the last day of the fiscal year ending after the fifth anniversary of this offering.

We have elected to take advantage of certain of the reduced disclosure obligations in this prospectus and may elect to take advantage of other reduced reporting requirements in future filings. As a result, the information that we provide to our investors may be different from the information you might receive from other public reporting companies that are not emerging growth companies in which you hold equity interests. It is possible that some investors will find our common stock less attractive as a result of our elections, which may cause a less active trading market for our common stock and more volatility in our stock price.

In addition, the JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. This allows an emerging growth company to delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. As an emerging growth company we have elected to not avail ourselves of this exemption; however, we could elect to do so in the future. In such event, we will not be subject to new or revised accounting standards at the same time that they become applicable to other public companies that are not emerging growth companies.

To the extent that we continue to qualify as a "smaller reporting company," as such term is defined in Rule 12b-2 under the Exchange Act, after we cease to qualify as an emerging growth company, we will continue to be permitted to make certain reduced disclosures in our periodic reports and other documents that we file with the SEC.

**THE OFFERING**

---

| | |
|:---|:---|
| **Securities offered by us:** | Units, with each Unit consisting of one (1) share of Common Stock and one (1) Warrant to purchase a share of Common Stock. The shares of Common Stock and the Warrants (to purchase up to shares of Common Stock) underlying the Units are immediately separable and will be issued separately in this offering. Warrants are exercisable upon issuance and expire sixty (60) days from issuance. The Warrants will be issued in registered form under a warrant agency agreement between the warrant agent and us. This prospectus also includes the offering of the shares of Common Stock issuable upon exercise of the Warrants. |
| **Common Stock outstanding before this offering:** | shares<sup>(1)</sup>. |
| **Common Stock outstanding after this offering:** | shares<sup>(1)</sup>. |
| **Use of proceeds:** | We intend to use the net proceeds from this offering for working capital and general corporate purposes. Please see the section entitled "<u>[Use of Proceeds](#s_006)</u>" on page <u>S-6</u> of this prospectus supplement for a more detailed discussion. |
| **Risk factors:** | An investment in our securities involves a high degree of risk. Please see the section entitled "<u>[Risk Factors](#s_005)</u>" beginning on page <u>S-5</u> of this prospectus supplement as well as the other information included in or incorporated by reference into this prospectus supplement and the accompanying prospectus for a discussion of factors that you should consider carefully before making an investment decision. |
| **Dividend policy:** | We have never declared or paid any cash dividends on our Common Stock. We do not anticipate paying any cash dividends in the foreseeable future. |
| **National Securities Exchange Listing:** | Our Common Stock is currently listed on the NYSE American under the symbol "CTM". |

---

(1) The number of shares of our Common Stock to be outstanding
after the offering is based on shares of Common Stock outstanding as of June [ ] , 2025 and excludes, as of that
date, the following:

● shares of Common Stock issuable upon conversion of Series A Preferred Stock;

● shares of Common Stock issuable upon conversion of Series C Preferred Stock;

● shares of Common Stock available for issuance under the Castellum, Inc. 2021 Stock Incentive Plan;

● shares of Common Stock issuable upon the exercise of options outstanding, with a weighted average exercise price of $ per share; and

● shares of Common Stock issuable upon the exercise of warrants outstanding, with a weighted average exercise price of $ per share.

**RISK FACTORS**

 

*Before making an investment decision, you should carefully consider the risks described in this prospectus supplement, together with all of the other information incorporated by reference into this prospectus supplement and the accompanying prospectus, including the risks described in our most recent Annual Report on Form 10-K, as well as any amendments thereto reflected in subsequent filings with the SEC, including our audited consolidated financial statements and corresponding management's discussion and analysis. The risks mentioned below are presented as of the date of this prospectus supplement and we expect that these will be updated from time to time in our periodic and current reports filed with or furnished to the SEC, as applicable, which are incorporated herein by reference. Please refer to these subsequent reports for additional information relating to the risks associated with investing in our securities.*

 

*Our business, financial condition or results of operations could be materially adversely affected by any of these risks. Additional risks not presently known to us or that we currently deem immaterial may also impair our business operations. The trading price of our Common Stock could decline due to any of these risks, and you may lose all or part of your investment. This prospectus supplement, the accompanying prospectus and the incorporated documents also contain forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks mentioned below. Forward-looking statements included in this prospectus supplement are based on information available to us on the date hereof, and all forward-looking statements in documents incorporated by reference are based on information available to us as of the date of each such document. We are under no obligation to update or alter such forward-looking statements whether as a result of new information, future events or otherwise, other than as required by applicable securities legislation.*

**Risks Relating to This Offering** 

 ****

***Sales of our Common Stock by stockholders may have an adverse effect on the then prevailing market price of our Common Stock.***

Sales of a substantial number of our Common Stock in the public market following this offering could cause the market price of our Common Stock to decline and could impair our ability to raise capital through the sale of additional equity securities. We cannot predict the effect that future sales of our Common Stock or other equity or equity-related securities would have on the market price of our Common Stock.

 ****

***Management will have broad discretion as to the use of the net proceeds from this offering, and we may not use the proceeds effectively.***

We intend to use the net proceeds from the sale of securities by us in this offering for working capital and general corporate purposes. Our management will have broad discretion as to the application of the net proceeds from this offering and could use them for purposes other than those contemplated at the time of this offering, as described below in the section entitled "Use of Proceeds," or in ways that do not necessarily improve our operating results or enhance the value of our Common Stock. Our stockholders may not agree with the manner in which our management chooses to allocate and spend the net proceeds. Our failure to use these funds effectively could have a material adverse effect on our business and could cause the price of our securities to decline.

 ****

***Investors in this offering will suffer immediate and substantial dilution in the net tangible book value per Common Stock.***

A purchaser of securities in this offering will experience immediate and substantial dilution. Please see the section entitled "Dilution" for a more detailed discussion of the dilution you will incur in this offering.

 ****

***We may require additional funding through further issuances of our Common Stock or other securities, which may negatively affect the market price of our Common Stock.***

To operate our business, we may need to raise additional capital through sales of our Common Stock, securities exercisable for or convertible into our Common Stock or debt securities pursuant to which interest and/or principal payments may be satisfied through the issuance of our Common Stock. Future sales of such securities or our Common Stock could adversely affect the prevailing market price of our Common Stock and our ability to raise capital in the future, and may cause you to incur additional dilution.

***We do not intend to pay dividends on our Common Stock so any returns will depend on appreciation in the price of our Common Stock.***

We have never declared or paid any cash dividends on our Common Stock. We currently anticipate that we will retain future earnings, if any, for the development, operation and expansion of our business and do not anticipate declaring or paying any cash dividends for the foreseeable future. Any return to stockholders will, therefore, be limited to the appreciation of their respective shares. There is no guarantee that our Common Stock will appreciate in value or maintain the price at which you purchased them.

**USE OF PROCEEDS**

We estimate that the net proceeds from this offering will be approximately $ after deducting the placement agent fees and commissions and estimated offering expenses payable by us, based upon the public offering price of $ per Unit. We currently expect to use the net proceeds from this offering for 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, and our management will retain broad discretion as to the ultimate allocation of the proceeds. We may temporarily invest funds that we do not immediately need for these purposes in investment securities or use them to make payments on our borrowings.

**DIVIDEND POLICY**

We have not declared or paid cash dividends on our common stock since our inception. Under Nevada law, we are prohibited from paying dividends if the distribution would result in our company not being able to pay its debts as they become due in the normal course of business, if our total assets would be less than the sum of our total liabilities plus the amount that would be needed to pay the dividends, or if we were to be dissolved at the time of distribution to satisfy the preferential rights upon dissolution of stockholders whose preferential rights are superior to those receiving the distribution. Even if our board of directors ("Board") decides to pay dividends, the form, the frequency, and the amount will depend upon our future operations and earnings, capital requirements and surplus, general financial condition, contractual restrictions and other factors that the Board may deem relevant. While our Board will make any future decisions regarding dividends, as circumstances surrounding us change, it currently does not anticipate that we will pay any cash dividends in the foreseeable future.

**DILUTION**

If you invest in our securities in this offering, your interest will be diluted immediately to the extent of the difference between the effective offering price per Unit and the as-adjusted net tangible book value per share of Common Stock after this offering.

The net tangible book value of our Common Stock as of March 31, 2025, was approximately $9.0 million, or approximately $0.104 per share of Common Stock. Net tangible book value per share represents the amount of our total tangible assets less total liabilities divided by the total number of our Common Stock outstanding as of March 31, 2025.

After giving effect to: (a) the exercise of an aggregate of 610,543 warrants at $1.08 per share for 610,543 shares of Common Stock during May 2025 which resulted in proceeds to the Company of $659,386 (b) an amendment to a promissory note with Robert Eisiminger to modify the terms of the promissory note, including a reduction of the principal balance by $2,000,000, (c) the repayment of the promissory note payable to the Buckhout Charitable Trust in the amount of $1,700,000 in June 2025, owed as of March 2025, and (d) the repayment of $60,000 since March 31, 2025, relating to our due to seller amount, our pro forma net tangible book value as of March 31, 2025 would have been approximately $9.5 million, or approximately $.110 per share of Common Stock.

After giving effect to the sale of shares of Common Stock and assuming the exercise of ___warrants for shares of Common Stock in this offering at an offering price of $ per Unit, our as adjusted net tangible book value as of March 31, 2025, would have been approximately $ million, or approximately $ per share of Common Stock. This represents an immediate increase in pro forma net tangible book value of approximately $ per share of Common Stock to our existing security holders and an immediate dilution in pro forma as adjusted net tangible book value of approximately $ per share of Common Stock to the purchaser of securities in this offering, as illustrated by the following table:

---

| | |
|:---|:---|
| Offering price per Unit | $— |
| Net tangible book value per share of Common Stock as of March 31, 2025 | $0.104 |
| Increase in pro forma net tangible book value per share of Common Stock attributable to pro forma adjustments | $0.006 |
| Pro forma net tangible book value per share of Common Stock as of March 31, 2025 | $0.110 |
| Increase in pro forma net tangible book value per share of Common Stock attributable to the offering | $- |
| Pro forma as adjusted net tangible book value per share of Common Stock as of March 31, 2025, after giving effect to this offering | $— |
| Dilution in pro forma as adjusted net tangible book value per share Common Stock to new investors participating in this offering | $— |

---

To the extent that outstanding exercisable options or warrants are exercised, you may experience further dilution. In addition, we may need to raise additional capital and to the extent that we raise additional capital by issuing equity or convertible debt securities your ownership will be further diluted.

**DESCRIPTION OF THE SECURITIES WE ARE OFFERING**

We are offering Units at an offering price of $ per Unit, with each Unit comprised of one (1) share of Common Stock and Warrant to purchase a share of Common Stock at an exercise of price of $.

**Common Stock**

The material terms and provisions of our Common Stock and each other class of our securities that qualifies or limits our Common Stock are described under the caption "<u>[Description of Common Stock](#a_007)</u>" starting on page <u>8</u> of the accompanying prospectus.

**Warrants**

The material terms and provisions of our Warrants and each other class of our securities that qualifies or limits our Common Stock are described under the caption "<u>[Description of Warrants](#a_007)</u>" starting on page <u>12</u> of the accompanying prospectus. The Warrants will be maintained by the Company's transfer agent, through a Warrant Agent Agreement.

**PLAN OF DISTRIBUTION**

Maxim Group LLC (the "Placement Agent") have agreed to act as the exclusive placement agent in connection with this offering. The Placement Agent is not purchasing or selling any of the Units offered by this prospectus supplement but will use their best efforts to arrange for the sale of the securities offered by this prospectus supplement.

Investors purchasing securities offered hereby will have the option to execute a securities purchase agreement with us. In addition to the rights and remedies available to all investors in this offering under federal and state securities laws, the investors which enter into a securities purchase agreement will also be able to bring claims of breach of contract against us. Investors who do not enter into a securities purchase agreement shall rely solely on this prospectus in connection with the purchase of our securities in this offering. The Placement Agent may engage one or more subagents or selected dealers in connection with this offering. The offering is expected to close on or about June , 2025, subject to customary closing conditions without further notice.

**Fees and Expenses** 

We have agreed to pay the Placement Agent an aggregate Placement Agents' fee of up to $ which represents (i) 7% of the aggregate purchase price of the shares of our Units sold in this offering and (ii) 3.5% of the aggregate purchase price paid pursuant to the exercise of the Warrants. The following table shows the per share and total cash Placement Agents' fees we will pay to the Placement Agent in connection with the sale of the Units offered pursuant to this prospectus supplement and the accompanying prospectus.

---

| | | |
|:---|:---|:---|
|  | **Per Unit** | **Total** |
| Public Offering Price and Proceeds, Before Expenses, to us | $| $|
| Placement Agent Fees | $| $|
| Proceeds before expenses | $| $|

---

(1) Does not include up to $
in proceeds to the Company upon exercise of the Warrants.

(2) Placement Agent will receive up to $ in additional fees upon
exercise of the Warrants.

(3) Does not include up to $ in
proceeds to the Company upon exercise of the Warrants.

In addition, subject to compliance with FINRA Rule 5110(f)(2)(D), we have agreed to reimburse the Placement Agent for all reasonable travel and other necessary out-of-pocket expenses of third parties incurred directly in connection with the placement agency agreement, including the fees and expenses of the Placement Agent's counsel of $. Any aggregate expense(s) in excess of $1,000 shall be approved by the Company in advance (provided, however, that such expense cap in no way limits or impairs the indemnification and contribution provisions of the placement agency agreement).

**Determination of Offering Price**

The public offering price of the Units we are offering was negotiated between us and the investors, in consultation with the Placement Agent based on the trading of our Common Stock prior to the offering, among other things. Other factors considered in determining the public offering price of the Units we are offering include the history and prospects of the Company, the stage of development of our business, our business plans for the future and the extent to which they have been implemented, an assessment of our management, general conditions of the securities markets at the time of the offering and such other factors as were deemed relevant.

**Indemnification**

We have agreed to indemnify the Placement Agent against liabilities under the Securities Act. We have also agreed to contribute to payments the Placement Agent may be required to make in respect of such liabilities.

The Placement Agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the resale of the shares sold by it while acting as principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the Placement Agent would be required to comply with the requirements of the Securities Act and the Exchange Act of 1934 (the "Exchange Act"), including, without limitation, Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M under the Exchange Act. These rules and regulations may limit the timing of purchases and sales of shares by the Placement Agent acting as principal. Under these rules and regulations, the Placement Agent may not engage in any stabilization activity in connection with our securities; and may not bid for or purchase any of our securities or attempt to induce any person to purchase any of our securities, other than as permitted under the Exchange Act, until it has completed its participation in the distribution.

**Lock-up Agreement**

Our executive officers and directors have agreed to a 60-day "lock-up." This means that, for a period of 60 days, as applicable, following such pricing date, subject to certain limited exceptions, such persons may not offer, sell, pledge or otherwise dispose of these securities without the prior written consent of the Placement Agent.

The Placement Agent has no present intention to waive or shorten the lock-up period; however, the terms of the lock-up agreements may be waived at its discretion. In determining whether to waive the terms of the lockup agreements, the Placement Agent may base its decision on its assessment of the relative strengths of the securities markets and companies similar to ours in general, and the trading pattern of, and demand for, our securities in general.

**Electronic Distribution**

This prospectus supplement may be made available in electronic format on websites or through other online services maintained by the Placement Agent, or by an affiliate. Other than this prospectus in electronic format, the information on the Placement Agent's website and any information contained in any other website maintained by the Placement Agent or by an affiliate is not part of this prospectus or the registration statement of which this prospectus supplement is a part, has not been approved and/or endorsed by us or the Placement Agent, and should not be relied upon by investors.

The foregoing does not purport to be a complete statement of the terms and conditions of the placement agency agreement or the securities purchase agreement, copies of which are incorporated by reference into the registration statement of which this prospectus is a part. See "Where You Can Find More Information."

**Regulation M Restrictions**

The Placement Agent may be deemed to be an underwriter within the meaning of Section 2(a)(11) of the Securities Act, and any commissions received by it and any profit realized on the resale of any shares of Common Stock sold by it while acting as a principal might be deemed to be underwriting discounts or commissions under the Securities Act. As an underwriter, the Placement Agent would be required to comply with the requirements of the Securities Act and the Securities Exchange Act of 1934, as amended, or the "Exchange Act," including Rule 415(a)(4) under the Securities Act and Rule 10b-5 and Regulation M promulgated under the Exchange Act.

These rules and regulations may limit the timing of purchases and sales of shares offered hereby by the Placement Agent acting as a principal. Under these rules and regulations, the Placement Agent:

● ordinary brokerage transactions and transactions in which the broker solicits purchasers;

● must not engage in any stabilization activity in connection with our securities; and

● must not bid for or purchase any of our securities or attempt to induce any person to purchase any of our securities, other than as permitted under the Exchange Act, until it has completed its participation in the distribution.

**Passive Market Making**

In connection with this offering, the Placement Agent may engage in passive market making transactions in our Common Stock on the Nasdaq Stock Market in accordance with Rule 103 of Regulation M promulgated under the Exchange Act during a period before the commencement of offers or sales of shares of our Common Stock and extending through the completion of the distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. If all independent bids are lowered below the passive market maker's bid, however, that bid must then be lowered when specified purchase limits are exceeded.

**Other**

From time to time, the Placement Agent and its affiliates may in the future provide various investment banking, financial advisory and other services to us and our affiliates for which services they may receive customary fees, but we have no present arrangements to do so. Subject to Regulation M and other applicable statutes and regulations, in the course of its businesses, the Placement Agent and its affiliates may actively trade our securities or loans for their own account or for the accounts of customers, and, accordingly, the Placement Agent may at any time hold long or short positions in such securities or loans.

The foregoing includes a brief summary of certain provisions of the placement agency agreement and securities purchase agreement that we will enter into and does not purport to be a complete statement of their terms and conditions. A copy of the placement agency agreement and the form of securities purchase agreement will be filed with the SEC and incorporated by reference into the registration statement of which this prospectus supplement forms a part. See "<u>[Where You Can Find More Information](#s_013)</u>" on page <u>S-13</u>.

**Listing**

Our Common Stock is listed on the NYSE American LLC under the symbol "CTM."

The Units have no stand-alone rights and will not be certificated or issued as stand-alone securities. The shares of Common Stock and the Warrants underlying the Units are immediately separable and will be issued separately in electronic form in this offering. We do not intend to apply for listing of the Warrants on any national securities exchange or other trading market, and we do not believe any such market will develop. Therefore, the liquidity of the Warrants will be limited and should be considered illiquid.

**LEGAL MATTERS**

Certain legal matters relating to the offering of the securities under this prospectus supplement will be passed upon for us by Lucosky Brookman LLP, Woodbridge, New Jersey. Pryor Cashman LLP, New York, New York is acting as counsel to the placement agent in connection with this offering.

**EXPERTS**

Our consolidated financial statements of as of December 31, 2024 and 2023 and for each of the years in the two-year period ended December 31, 2024 incorporated in this Prospectus by reference from the Company's Annual Report on Form 10-K for the year ended December 31, 2024 have been audited by RSM US LLP, an independent registered public accounting firm, as stated in their reports thereon, incorporated herein by reference, and have been incorporated in this Prospectus and Registration Statement in reliance upon such report and upon the authority of such firm as experts in accounting and auditing.

**WHERE YOU CAN FIND MORE INFORMATION**

We file annual, quarterly and periodic reports, proxy statements, and other information with the SEC using the SEC's Electronic Data Gathering, Analysis, and Retrieval ("EDGAR") system. The SEC maintains a web site that contains reports, proxy and information statements, and other information about issuers, such as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our website address is www.castellumus.com. The information on 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. This prospectus omits some of the information contained in the registration statement, and we refer you to the full registration statement for further information about us and the securities being offered by the selling stockholders under this prospectus. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the documents establishing the terms of the offered securities are or may be filed as exhibits to 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 DOCUMENTS BY REFERENCE**

**Incorporation by Reference**

We are "incorporating by reference" in this prospectus certain documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information in the documents incorporated by reference is considered to be part of this prospectus. Statements contained in documents that we file with the SEC and that are incorporated by reference in this prospectus will automatically update and supersede information contained in this prospectus, including information in previously filed documents or reports that have been incorporated by reference in this prospectus, to the extent the new information differs from or is inconsistent with the old information. We have filed or may file the following documents with the SEC and they are incorporated herein by reference as of their respective dates of filing.

● Our Annual Report on [Form 10-K](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000021/ctm-20241231.htm) for the year ended December 31, 2024, filed with the SEC on March 11, 2025;

● Our Quarterly Report on [Form 10-Q](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000050/ctm-20250331.htm) for the period ended March 31, 2025, filed with the SEC on May 9, 2025;

● The portions of the definitive proxy statement on [Schedule 14A](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000037/ctmproxystatementfinal0411.htm) filed on April 11, 2025 for the Company's 2025 Annual Meeting of Stockholders held on May 28, 2025 that are incorporated by reference into the Company's Annual Report on [Form 10-K](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000021/ctm-20241231.htm) for the fiscal year ended December 31, 2024;

● Our Current Reports on Form 8-K or Form 8-K/A filed (not furnished) with the SEC on [January 8, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000004/ctm-20250108.htm) , [January 14, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000006/ctm-20250114.htm) , [February 25, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000011/ctm-20250225.htm) , [February 28, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000013/ctm-20250227.htm) , [March 12, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000023/ctm-20250312.htm) , [March 18, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000162828025013445/ctm-20250314.htm) , [March 19, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000025/ctm-20250319.htm) , [April 4, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000030/ctm-20250331.htm) , [April 10, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000034/ctm-20250410.htm) , [April 15, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000042/ctm-20250415.htm) , [April 21, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000044/ctm-20250417.htm) , [May 28, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000056/ctm-20250528.htm) , [June 2, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000058/ctm-20250602.htm) , and [June 6, 2025](http://www.sec.gov/Archives/edgar/data/1877939/000187793925000060/ctm-20250605.htm) .

● The description of our common stock, par value $0.0001 per share (the "Common Stock") contained in our Registration Statement on [Form 8-A](http://www.sec.gov/Archives/edgar/data/1877939/000157587222000931/lb015_8a-12b.htm) , filed with the SEC on October 6, 2022 and any amendment or report filed for the purpose of updating such description.

All documents that we filed with the SEC pursuant to Sections 13(a), 13(c), 14, and 15(d) of the Exchange Act subsequent to the date of this registration statement and prior to the filing of a post-effective amendment to this registration statement that indicates that all securities offered under this prospectus have been sold, or that deregisters all securities then remaining unsold, will be deemed to be incorporated in this registration statement by reference and to be a part hereof from the date of filing of such documents.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus shall be deemed modified, superseded, or replaced for purposes of this prospectus to the extent that a statement contained in this prospectus, or in any subsequently filed document that also is deemed to be incorporated by reference in this prospectus, modifies, supersedes, or replaces such statement. Any statement so modified, superseded, or replaced shall not be deemed, except as so modified, superseded, or replaced, to constitute a part of this prospectus. None of the information that we disclose under Items 2.02 or 7.01 of any Current Report on Form 8-K or any corresponding information, either furnished under Item 9.01 or included as an exhibit therein, that we may from time to time furnish to the SEC will be incorporated by reference into, or otherwise included in, this prospectus, except as otherwise expressly set forth in the relevant document. Subject to the foregoing, all information appearing in this prospectus is qualified in its entirety by the information appearing in the documents incorporated by reference.

**PROSPECTUS**

**CASTELLUM, INC.**

**$100,000,000 of** 

**Common Stock**

**Preferred Stock**

**Warrants**

**Rights**

**Units**

**Debt Securities**

**Offered by the Company**

We may offer and sell up to $100 million in the aggregate of the securities identified above from time to time in one or more offerings.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering, as well as 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 and the applicable prospectus supplement before you invest in 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. 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 the applicable prospectus supplement. See the sections of this prospectus entitled "About this Prospectus" and "Plan of Distribution" for more 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 INVOLVES RISKS. SEE THE "<u>[RISK FACTORS](#a_004)</u>" ON PAGE <u>5</u> AND THE RISK FACTORS IN OUR MOST RECENT ANNUAL REPORT ON FORM 10-K, WHICH IS INCORPORATED BY REFERENCE HEREIN, AS WELL AS IN ANY OTHER RECENTLY FILED QUARTERLY OR CURRENT REPORTS AND, IF ANY, IN THE RELEVANT PROSPECTUS SUPPLEMENT. WE URGE YOU TO CAREFULLY READ THIS PROSPECTUS AND THE ACCOMPANYING PROSPECTUS SUPPLEMENT, TOGETHER WITH THE DOCUMENTS WE INCORPORATE BY REFERENCE, DESCRIBING THE TERMS OF THESE SECURITIES BEFORE INVESTING.**

The aggregate market value of our outstanding common stock held by non-affiliates is $143,278,804 based on 76,482,629 shares of outstanding common stock, of which 20,948,209 are held by affiliates, and a per share price of $2.58 based on the closing sale price of our common stock on December 30, 2024.

Our common stock is listed on the NYSE American LLC (the "NYSE American") under the symbol "CTM". On January 8, 2025, the last reported sale price of our common stock on the NYSE American was $1.14 per share.

**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. Any representation to the contrary is a criminal offense.**

**The date of this prospectus is January 22, 2025.** 

**TABLE OF CONTENTS**

---

| | |
|:---|:---|
|  | **Page** |
| [ABOUT THIS PROSPECTUS](#a_001) | 1 |
| [WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE](#a_002) | 2 |
| [THE COMPANY](#a_003) | 4 |
| [RISK FACTORS](#a_004) | 5 |
| [SPECIAL NOTICE REGARDING FORWARD-LOOKING STATEMENTS](#a_005) | 6 |
| [USE OF PROCEEDS](#a_006) | 7 |
| [DESCRIPTION OF CAPITAL STOCK](#a_007) | 8 |
| [DESCRIPTION OF PREFERRED STOCK](#a_008) | 10 |
| [DESCRIPTION OF WARRANTS](#a_009) | 12 |
| [DESCRIPTION OF RIGHTS](#a_010) | 13 |
| [DESCRIPTION OF UNITS](#a_011) | 14 |
| [DESCRIPTION OF DEBT SECURITIES](#a_012) | 15 |
| [PLAN OF DISTRIBUTION](#a_013) | 17 |
| [LEGAL MATTERS](#a_014) | 19 |
| [EXPERTS](#a_015) | 19 |

---

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. By using a shelf registration statement, we may sell securities from time to time and in one or more offerings up to a total dollar amount of $100,000,000 as described in this prospectus.

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. The prospectus supplement may also add, update, or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement, you should rely on the prospectus supplement. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement, together with the additional information described under the heading "Where You Can Find More Information; Incorporation by Reference."

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 on it. 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 as of the date on its respective cover, 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.

When we refer to "Castellum," "we," "our," "us," and the "Company" in this prospectus, we mean Castellum, Inc., unless otherwise specified. When we refer to "you," we mean the holders of the applicable series of securities.

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

**Available Information**

We file annual, quarterly and periodic reports, proxy statements, and other information with the SEC using the SEC's Electronic Data Gathering, Analysis, and Retrieval ("EDGAR") system. The SEC maintains a web site that contains reports, proxy and information statements, and other information about issuers, such as us, who file electronically with the SEC. The address of that website is *http://www.sec.gov*.

Our website address is *<u>www.castellumus.com</u>*. The information on 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. This prospectus omits some of the information contained in the registration statement, and we refer you to the full registration statement for further information about us. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the documents establishing the terms of the offered securities are or may be filed as exhibits to 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 by Reference**

We are "incorporating by reference" in this prospectus certain documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information in the documents incorporated by reference is considered to be part of this prospectus. Statements contained in documents that we file with the SEC and that are incorporated by reference in this prospectus will automatically update and supersede information contained in this prospectus, including information in previously filed documents or reports that have been incorporated by reference in this prospectus, to the extent the new information differs from or is inconsistent with the old information. We have filed or may file the following documents with the SEC and they are incorporated herein by reference as of their respective dates of filing.

● Our Annual Report on [Form 10-K](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000018/ctm-20231231.htm) for the year ended December 31, 2023, filed with the SEC on March 21, 2024;

● The portions of the definitive proxy statement on Schedule 14A filed on April 16, 2024 for the Company's 2024 Annual Meeting of Stockholders held on May 29, 2024 that are incorporated by reference into the Company's Annual Report on [Form 10-K](http://www.sec.gov/Archives/edgar/data/1877939/000187793924000018/ctm-20231231.htm) for the fiscal year ended December 31, 2023;

● Our Quarterly Report on [Form 10-Q](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000036/ctm-20240331.htm) for the period ended March 31, 2024, filed with the SEC on May 15, 2024;

● Our Quarterly Report on [Form 10-Q](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000060/ctm-20240630.htm) for the period ended June 30, 2024, filed with the SEC on August 9, 2024;

● Our Quarterly Report on [Form 10-Q](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000077/ctm-20240930.htm) for the period ended September 30, 2024, filed with the SEC on November 13, 2024;

● Our Current Reports on Form 8-K or Form 8-K/A filed (not furnished) with the SEC on [January 29, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000162828024002401/ctm-20240125.htm) , [January 30, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000003/ctm-20240129.htm) , [February 23, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000011/ctm-20240222.htm) , [March 21, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000020/ctm-20240321.htm) , [April 18, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000032/ctm-20240418.htm) , [May 29, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000041/ctm-20240529.htm) , [June 6, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000043/ctm-20240606.htm) , [June 7, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000046/ctm-20240607.htm) , [July 3, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000049/ctm-20240701.htm) , [July 10, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000051/ctm-20240710.htm) , [July 17, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000053/ctm-20240717.htm) , [July 22, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000055/ctm-20240722.htm) , [September 3, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000066/ctm-20240901.htm) , [September 4, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000069/ctm-20240902.htm) , [September 24, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000187793924000071/ctm-20240924.htm) , [December 26, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000162828024052385/ctm-20241222.htm) , and [December 30, 2024](https://www.sec.gov/Archives/edgar/data/1877939/000162828024052536/ctm-20241226.htm) ; and

● The description of our common stock, par value $0.0001 per share (the "Common Stock") contained in our Registration Statement on [Form 8-A](http://www.sec.gov/Archives/edgar/data/1877939/000157587222000931/lb015_8a-12b.htm) , filed with the SEC on October 6, 2022 and any amendment or report filed for the purpose of updating such description.

All documents that we filed with the SEC pursuant to Sections 13(a), 13(c), 14, and 15(d) of the Exchange Act subsequent to the date of this registration statement and prior to the filing of a post-effective amendment to this registration statement that indicates that all securities offered under this prospectus have been sold, or that deregisters all securities then remaining unsold, will be deemed to be incorporated in this registration statement by reference and to be a part hereof from the date of filing of such documents.

Any statement contained in a document incorporated or deemed to be incorporated by reference in this prospectus shall be deemed modified, superseded, or replaced for purposes of this prospectus to the extent that a statement contained in this prospectus, or in any subsequently filed document that also is deemed to be incorporated by reference in this prospectus, modifies, supersedes, or replaces such statement. Any statement so modified, superseded, or replaced shall not be deemed, except as so modified, superseded, or replaced, to constitute a part of this prospectus. None of the information that we disclose under Items 2.02 or 7.01 of any Current Report on Form 8-K or any corresponding information, either furnished under Item 9.01 or included as an exhibit therein, that we may from time to time furnish to the SEC will be incorporated by reference into, or otherwise included in, this prospectus, except as otherwise expressly set forth in the relevant document. Subject to the foregoing, all information appearing in this prospectus is qualified in its entirety by the information appearing in the documents incorporated by reference.

You may request a free copy of any of the documents incorporated by reference in this prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:

**Castellum, Inc.**

**1934 Old Gallows Road, Suite 350**

**Vienna, VA 22182**

**Telephone: (703) 752-6157** 

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement and the information on our website is not a part of this prospectus and is not incorporated by reference.

**THE COMPANY**

**Overview**

Castellum, Inc. is focused on building a large, successful technology company in the areas of cybersecurity, IT, electronic warfare, information warfare, and information operations with businesses in the defense, federal, civilian, and commercial markets. Services include intelligence analysis, software development, software engineering, program management, strategic and mission planning, information assurance, cybersecurity and policy support, data analytics, and model based systems engineering. These services are applicable to customers in the United States government ("USG"), financial services, healthcare, and other users of large data applications. They can be delivered to on-premises enclaves or customers who rely upon cloud-based infrastructures. The Company has worked with multiple business brokers and contacts within their business network to identify potential acquisitions. Due to our success in completing seven acquisitions over the previous five years and given our executive officers' and key managers' networks of contacts in the IT, telecom, cybersecurity, and defense sectors, we believe that we are well positioned to continue to execute our business strategy given a pipeline of identified and acquisition targets. Because of our executive officers' and key managers' prior experience growing businesses organically, we believe that we are well positioned to grow our existing business via internal growth as well. The Company has developed a qualified business opportunity (the "Opportunity Pipeline"). Although there can be no assurance that the Opportunity Pipeline can be converted to revenues, the Company believes that the total value of the Opportunity Pipeline was approximately $738 million as of September 30, 2024. The Opportunity Pipeline represents the revenue opportunity for the Company from potential future contracts obtained through organic growth from qualified customers based on the expected base year contract value plus the value of all option periods.

We provide expertise and technology to enterprise and mission customers in support of national security missions and government modernization/transformation. Due to the nature of the work being executed for the USG the budgets are expected to continue to grow in support of bipartisan national security imperatives. The majority of contracted work is operational in nature and is funded on an on-going basis.

As a government contractor, Castellum both cooperates (as a teaming partner) and competes with many different companies. Sometimes, Castellum both teams with (on one contract) and competes against (on a different contract) the same company. Among others, Castellum competes with (and sometimes also teams with) Northrup Grumman, CACI, Peraton, and Booz-Allen Hamilton.

**Corporate Information**

The Company was incorporated in Nevada on September 30, 2010 under the name Passionate Pet, Inc. and in January 2013, the Company changed its name to Firstin Wireless Technology, Inc. In March 2015, the Company changed its name to BioNovelus, Inc. On June 12, 2019, the Company acquired Bayberry Acquisition Corporation, a Nevada corporation ("Bayberry" and, as context requires, the "Bayberry Acquisition"). On February 23, 2021, Bayberry was dissolved with the Nevada Secretary of State as it was non-operational after the merger with the Company. On November 21, 2019, we acquired Corvus Consulting, LLC, ("Corvus"), a Virginia limited liability company. On December 26, 2019, following our acquisition of Corvus, we changed our name from BioNovelus, Inc. to Castellum, Inc.

Our principal executive offices are located at 1934 Old Gallows Road, Suite 350, Vienna, VA 22182. Our telephone number is (703) 752-6157 and our website address is *<u>www.castellumus.com</u>*. Our website and the information contained on, or accessible through, our website will not be deemed to be incorporated by reference into this prospectus and does not constitute part of this prospectus.

**RISK FACTORS**

Investing in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should carefully consider the risk factors we describe in any prospectus supplement and in any related free writing prospectus for a specific offering of securities, as well as those incorporated by reference into this prospectus and any prospectus supplement. You should also carefully consider other information contained and incorporated by reference in this prospectus and any applicable prospectus supplement, including our financial statements and the related notes thereto incorporated by reference in this prospectus. The risks and uncertainties described in the applicable prospectus supplement and our other filings with the SEC incorporated by reference herein are not the only ones we face. Additional risks and uncertainties not presently known to us or that we currently consider immaterial may also adversely affect us. If any of the described risks occur, our business, financial condition, or results of operations could be materially harmed. In such case, the value of our securities could decline and you may lose all or part of your investment.

**SPECIAL NOTICE REGARDING FORWARD-LOOKING STATEMENTS**

This prospectus and the documents incorporated by reference herein contain or may contain forward looking statements that involve risks and uncertainties. All statements other than statements of historical fact contained in this prospectus, including statements regarding future events, our future financial performance, business strategy and plans and objectives of management for future operations, are forward-looking statements. We have attempted to identify forward-looking statements by terminology including "anticipates," "believes," "can," "continue," "could," "estimates," "expects," "intends," "may," "plans," "potential," "predicts," "should," or "will" or the negative of these terms or other comparable terminology. Although we do not make forward looking statements unless we believe we have a reasonable basis for doing so, we cannot guarantee their accuracy. These statements are only predictions and involve known and unknown risks, uncertainties and other factors, including the risks outlined under "Risk Factors" or elsewhere in this prospectus, which may cause our or our industry's actual results, levels of activity, performance or achievements expressed or implied by these forward-looking statements.

Forward-looking statements should not be read as a guarantee of future performance or results, and will not necessarily be accurate indications of the times at, or by which, that performance or those results will be achieved. Forward-looking statements are based on information available at the time they are made and/or management's good faith 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 what is expressed in or suggested by the forward-looking statements.

Forward-looking statements speak only as of the date they are made. You should not put undue reliance on any forward-looking statements. Except as required by law, we assume no obligation to update forward-looking statements to reflect actual results, changes in assumptions, or changes in other factors affecting forward-looking information, except to the extent required by applicable securities laws. If we do update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

**USE OF PROCEEDS**

We intend to use the net proceeds from the sale of the securities as set forth in the applicable prospectus supplement.

**DESCRIPTION OF COMMON STOCK**

The following description of our capital stock is not complete and may not contain all the information you should consider before investing in our capital stock. This description is summarized from, and qualified in its entirety by reference to, our Articles of Incorporation, as amended and Bylaws, as amended which have been publicly filed with the SEC. See "Where You Can Find More Information; Incorporation by Reference."

**Description of Common Stock**

The Company is authorized to issue 3,050,000,000 shares of capital stock, par value $0.0001 per share, of which 3,000,000,000 are shares of Common Stock and 50,000,000 are shares of preferred stock. As of January 8, 2025, there were 77,311,157 shares of Common Stock issued and outstanding.

Each share of our Common Stock entitles its holder to one vote in the election of each director and on all other matters voted on generally by our stockholders, other than any matter that (1) solely relates to the terms of any outstanding series of preferred stock or the number of shares of that series and (2) does not affect the number of authorized shares of preferred stock or the powers, privileges, and rights pertaining to the Common Stock. No share of our Common Stock affords any cumulative voting rights. This means that the holders of a majority of the voting power of the shares voting for the election of directors can elect all directors to be elected if they choose to do so.

Holders of our Common Stock will be entitled to dividends in such amounts and at such times as our Board of Directors in its discretion may declare out of funds legally available for the payment of dividends. We currently intend to retain our entire available discretionary cash flow to finance the growth, development, and expansion of our business and do not anticipate paying any cash dividends on the Common Stock in the foreseeable future. Any future dividends will be paid at the discretion of our Board of Directors.

If we liquidate or dissolve our business, the holders of our Common Stock will share ratably in all our assets that are available for distribution to our stockholders after our creditors are paid in full and the holders of all series of our outstanding preferred stock, if any, receive their liquidation preferences in full.

Our Common Stock has no preemptive rights and is not convertible or redeemable or entitled to the benefits of any sinking or repurchase fund.

The Common Stock is listed on the NYSE American under the trading symbol "CTM."

The Company's transfer agent is Nevada Agency and Transfer Company with an address at 50 West Liberty Street, Suite 880, Reno, NV 89501 and a phone number of (775) 322-0626.

 ****

***Anti-Takeover Provisions***

 

*Business Combinations*

The "business combination" provisions of Sections 78.411 to 78.444, inclusive, of the Nevada Revised Statutes, or NRS, generally prohibit a Nevada corporation with at least 200 stockholders of record, a "resident domestic corporation," from engaging in various "combination" transactions with any "interested stockholder" unless certain conditions are met or the corporation has elected in its articles of incorporation to not be subject to these provisions. We have not elected to opt out of these provisions and if we meet the definition of resident domestic corporation, now or in the future, our company will be subject to these provisions.

A "combination" is generally defined to include (a) a merger or consolidation of the resident domestic corporation or any subsidiary of the resident domestic corporation with the interested stockholder or affiliate or associate of the interested stockholder; (b) any sale, lease, exchange, mortgage, pledge, transfer, or other disposition, in one transaction or a series of transactions, by the resident domestic corporation or any subsidiary of the resident domestic corporation to or with the interested stockholder or affiliate or associate of the interested stockholder having: (i) an aggregate market value equal to 5% or more of the aggregate market value of the assets of the resident domestic corporation, (ii) an aggregate market value equal to 5% or more of the aggregate market value of all outstanding shares of the resident domestic corporation, or (iii) 10% or more of the earning power or net income of the resident domestic corporation; (c) the issuance or transfer in one transaction or series of transactions of shares of the resident domestic corporation or any subsidiary of the resident domestic corporation having an aggregate market value equal to 5% or more of the resident domestic corporation to the interested stockholder or affiliate or associate of the interested stockholder; and (d) certain other transactions with an interested stockholder or affiliate or associate of the interested stockholder.

An "interested stockholder" is generally defined as a person who, together with affiliates and associates, owns (or within two years, did own) 10% or more of a corporation's voting stock. An "affiliate" of the interested stockholder is any person that directly or indirectly through one or more intermediaries is controlled by or is under common control with the interested stockholder. An "associate" of an interested stockholder is any (a) corporation or organization of which the interested stockholder is an officer or partner or is directly or indirectly the beneficial owner of 10% or more of any class of voting shares of such corporation or organization; (b) trust or other estate in which the interested stockholder has a substantial beneficial interest or as to which the interested stockholder serves as trustee or in a similar fiduciary capacity; or (c) relative or spouse of the interested stockholder, or any relative of the spouse of the interested stockholder, who has the same home as the interested stockholder.

If applicable, the prohibition is for a period of two years after the date of the transaction in which the person became an interested stockholder, unless such transaction is approved by the board of directors prior to the date the interested stockholder obtained such status; or the combination is approved by the board of directors and thereafter is approved at a meeting of the stockholders by the affirmative vote of stockholders representing at least 60% of the outstanding voting power held by disinterested stockholders; and extends beyond the expiration of the two-year period, unless (a) the combination was approved by the board of directors prior to the person becoming an interested stockholder; (b) the transaction by which the person first became an interested stockholder was approved by the board of directors before the person became an interested stockholder; (c) the transaction is approved by the affirmative vote of a majority of the voting power held by disinterested stockholders at a meeting called for that purpose no earlier than two years after the date the person first became an interested stockholder; or (d) if the consideration to be paid to all stockholders other than the interested stockholder is, generally, at least equal to the highest of: (i) the highest price per share paid by the interested stockholder within the three years immediately preceding the date of the announcement of the combination or in the transaction in which it became an interested stockholder, whichever is higher, plus compounded interest and less dividends paid, (ii) the market value per share of common shares on the date of announcement of the combination and the date the interested stockholder acquired the shares, whichever is higher, plus compounded interest and less dividends paid, or (iii) for holders of preferred stock, the highest liquidation value of the preferred stock, plus accrued dividends, if not included in the liquidation value. With respect to (i) and (ii) above, the interest is compounded at the rate for one-year United States Treasury obligations from time to time in effect.

Applicability of the Nevada business combination statute would discourage parties interested in taking control of our company if they cannot obtain the approval of our Board. These provisions could prohibit or delay a merger or other takeover or change in control attempt and, accordingly, may discourage attempts to acquire our company even though such a transaction may offer our stockholders the opportunity to sell their stock at a price above the prevailing market price.

 

*Control Share Acquisitions*

The "control share" provisions of Sections 78.378 to 78.3793, inclusive, of the NRS, apply to "issuing corporations" that are Nevada corporations with at least 200 stockholders of record, including at least 100 stockholders of record who are Nevada residents, and that conduct business directly or indirectly in Nevada, unless the corporation has elected to not be subject to these provisions.

The control share statute prohibits an acquirer of shares of an issuing corporation, under certain circumstances, from voting its shares of a corporation's stock after crossing certain ownership threshold percentages, unless the acquirer obtains approval of the target corporation's disinterested stockholders. The statute specifies three thresholds: (a) one-fifth or more but less than one-third, (b) one-third but less than a majority, and (c) a majority or more, of the outstanding voting power. Generally, once a person acquires shares in excess of any of the thresholds, those shares and any additional shares acquired within 90 days thereof become "control shares" and such control shares are deprived of the right to vote until disinterested stockholders restore the right. These provisions also provide that if control shares are accorded full voting rights and the acquiring person has acquired a majority or more of all voting power, all other stockholders who do not vote in favor of authorizing voting rights to the control shares are entitled to demand payment for the fair value of their shares in accordance with statutory procedures established for dissenters' rights.

A corporation may elect to not be governed by, or "opt out" of, the control shares provisions by making an election in its articles of incorporation or bylaws, provided that the opt-out election must be in place on the 10th day following the date an acquiring person has acquired a controlling interest, that is, crossing any of the three thresholds described above. We have not opted out of these provisions and will be subject to the control share provisions of the NRS if we meet the definition of an issuing corporation upon an acquiring person acquiring a controlling interest unless we later opt out of these provisions and the opt out is in effect on the 10th day following such occurrence.

The effect of the Nevada control share statute is that the acquiring person, and those acting in association with the acquiring person, will obtain only such voting rights in the control shares as are conferred by a resolution of the stockholders at an annual or special meeting. The Nevada control share law, if applicable, could have the effect of discouraging takeovers of our company.

**DESCRIPTION OF PREFERRED STOCK** 

Our Articles of Incorporation empowers our board of directors, without action by our shareholders, to issue up to 50,000,000 shares of preferred stock. The Company has designated a total of 30,000,000 shares of preferred stock in the form of Series A Preferred Stock, Series B Preferred Stock, and Series C Preferred Stock. The board may, without action by our shareholders, from time to time, issue up to 20,000,000 more shares of preferred stock in one or more series, which preferred stock may be offered by this prospectus and supplements thereto.

**Series A Preferred Stock**

The Company has designated 10,000,000 shares of Series A Preferred Stock, par value of $0.0001. As of January 8, 2025, the Company has 5,875,000 shares of Series A Preferred Stock issued and outstanding, which is convertible into 587,500 shares of Common Stock. The holders of our Series A Preferred Stock are entitled to vote on an as-converted basis. Holders of the Series A preferred stock are entitled to receive a dividend of $0.0125 per year, one-twelfth of which shall be payable each calendar month. The Series A preferred stock has no maturity date or scheduled redemption date but may be redeemed at the Company's option at $1 per share at any time upon 30 days advanced written notice.. There is no sinking fund provisions applicable to the Series A preferred stock. Holders of Series A preferred stock are entitled to receive liquidation preference *pari passu* with the holders of Series B preferred stock and Series C preferred stock and prior to and in preference to any distribution of any of the assets of the Company to the holders of common stock.

**Series B Preferred Stock**

The Company has designated 10,000,000 shares of Series B Preferred Stock, par value of $0.0001. As of January 8, 2025, the Company has 0 shares of Series B Preferred Stock issued and outstanding.

**Series C Preferred Stock**

The Company has designated 10,000,000 shares of Series C Preferred Stock, par value of $0.0001. As of January 8, 2025, the Company has 570,000 shares of Series C Preferred Stock issued and outstanding, which are convertible into 356,250 shares of the Company's common stock. The holders of our Series C Preferred Stock are entitled to vote on an as-converted basis. The Series C preferred stock has a stated value of $1. Holders of the Series C preferred stock are entitled to receive cumulative dividends and distributions at a rate of 6%, paid at the rate of 0.5% per month. Holders of the Series C preferred stock received two shares of common stock of the Company for every one share of Series C preferred stock issued. At any time after July 16, 2028 the Company has the right to redeem all of the issued and outstanding shares of Series C preferred stock at a redemption price per preferred share equal to the stated value of $1. The Series C preferred stock has no maturity date or scheduled redemption date. There is no sinking fund provisions applicable to the Series C preferred stock. Holders of the Series C preferred stock are entitled to receive liquidation preference, *pari passu* with the holders of Series A preferred stock and Series B preferred stock and prior to and in preference to any distribution of any of the assets of the Company to the holders of common stock.

We will fix the rights, preferences, privileges, and restrictions of the preferred stock of each series in the certificate of designation relating to that series. We will file as an exhibit to the registration statement of which this prospectus is a part or will incorporate by reference from a current report on Form 8-K 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 the related series of preferred stock. This description will include any or all of the following, as required:

● 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;

● any contractual limitations on our ability to declare, set aside, or pay any dividends;

● the procedures for any auction and remarketing, if any;

● 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;

● any listing of the preferred stock on any securities exchange or market;

● 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;

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

● preemptive rights, if any;

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

● whether interests in the preferred stock will be represented by depositary shares;

● a discussion of any material or special 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 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.

If we issue shares of preferred stock under this prospectus, after receipt of payment therefor, the shares will be fully paid and non-assessable.

The Nevada Revised Statues provide that the holders of preferred stock will have the right to vote separately as a class on any proposal involving fundamental changes in the rights of holders of that preferred stock. This right is in addition to any voting rights provided for in the applicable certificate of designation.

Our board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of our common stock. Preferred stock could be issued quickly with terms designed to delay or prevent a change in control of our Company or make removal of management more difficult. Additionally, the issuance of preferred stock could have the effect of decreasing the market price of our common stock.

**DESCRIPTION OF WARRANTS**

We may offer to sell warrants from time to time. If we do so, we will describe the specific terms of the warrants in a prospectus supplement. In particular, we may issue warrants for the purchase of Common Stock or preferred stock in one or more series. We may also issue warrants independently or together with other securities and the warrants may be attached to or separate from those securities.

We will evidence each series of warrants by warrant certificates that we will issue under a separate agreement. We will enter into the warrant agreement with a warrant agent. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

We will describe in the applicable prospectus supplement the terms of the series of warrants, 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 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 agreement 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 agreement and warrants may be modified;

● certain 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 material terms, preferences, rights, or limitations of or restrictions on the warrants.

Holders may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with other requested 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 in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If a holder exercises fewer than all of the warrants represented by the warrant certificate, then we will issue a new warrant certificate for the remaining amount of warrants.

Holders will not have any of the rights of the holders of the securities purchasable upon the exercise of warrants until you exercise them. Accordingly, holders will not be entitled to, among other things, vote or receive dividend payments or similar distributions on the securities you can purchase upon exercise of the warrants.

The information provided above is only a summary of the terms under which we may offer warrants for sale. Accordingly, investors must carefully review the applicable warrant agreement for more information about the specific terms and conditions of these warrants before investing in us. In addition, please carefully review the information provided in the applicable prospectus supplement, which contains additional information that is important for you to consider in evaluating an investment in our securities.

**DESCRIPTION OF RIGHTS**

We may issue rights to our stockholders to purchase shares of our Common Stock or preferred stock described in this prospectus. We may offer rights separately or together with one or more additional rights, preferred stock, Common Stock, warrants, or any combination of those securities in the form of units, as described in the applicable prospectus supplement. Each series of rights will be issued under a separate rights agreement to be entered into between us and a bank or trust company, as rights agent. The rights agent for any rights we offer will be set forth in the applicable prospectus supplement. The rights agent will act solely as our agent in connection with the certificates relating to the rights of the series of certificates and will not assume any obligation or relationship of agency or trust for or with any holders of rights certificates or beneficial owners of rights. The following description sets forth certain general terms and provisions of the rights to which any prospectus supplement may relate. The particular terms of the rights to which any prospectus supplement may relate and the extent, if any, to which the general provisions may apply to the rights so offered will be described in the applicable prospectus supplement. To the extent that any particular terms of the rights, rights agreement, or rights certificates described in a prospectus supplement differ from any of the terms described below, then the terms described below will be deemed to have been superseded by that prospectus supplement. We encourage you to read the applicable rights agreement and rights certificate for additional information before you decide whether to purchase any of our rights.

The prospectus supplement relating to any rights that we offer will include specific terms relating to the offering, including, among other matters:

● the date of determining the stockholders entitled to the rights distribution;

● the aggregate number of shares of Common Stock, preferred stock, or other securities purchasable upon exercise of the rights;

● the exercise price;

● the aggregate number of rights issued;

● whether the rights are transferrable and the date, if any, on and after which the rights may be separately transferred;

● the date on which the right to exercise the rights will commence, and the date on which the right to exercise the rights will expire;

● the method by which holders of rights will be entitled to exercise;

● the conditions to the completion of the offering;

● the withdrawal, termination, and cancellation rights;

● whether there are any backstop or standby purchaser or purchasers and the terms of their commitment;

● whether stockholders are entitled to oversubscription rights;

● any U.S. federal income tax considerations; and

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

If less than all of the rights issued in any rights offering are exercised, we may offer any unsubscribed 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 arrangements, as described in the applicable prospectus supplement. In connection with any rights offering, we may enter into a standby underwriting or other arrangement with one or more underwriters or other persons pursuant to which such underwriters or other persons would purchase any offered securities remaining unsubscribed for after such rights offering.

**DESCRIPTION OF UNITS**

We may issue units consisting of any combination of the other types of securities offered under this prospectus in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units.

The following description, together with the additional information included in any applicable prospectus supplement, summarizes the general features of the units that we may offer under this prospectus. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of units being offered, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions and we will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from another report that we file with the SEC, the form of each unit agreement relating to units offered under this prospectus.

If we offer any units, certain terms of that series of units will be described in the applicable prospectus supplement, including, without limitation, the following, as applicable:

● the title of the series of units;

● identification and description of the separate constituent securities comprising the units;

● the price or prices at which the units will be issued;

● the date, if any, on and after which the constituent securities comprising the units will be separately transferable;

● a discussion of certain United States federal income tax considerations applicable to the units; and

● any other terms of the units and their constituent securities.

**DESCRIPTION OF DEBT SECURITIES**

As used in this prospectus, debt securities means the debentures, notes, bonds and other evidences of indebtedness that we may issue from time to time. The debt securities may be either be senior debt securities or subordinated debt securities and may be secured or unsecured obligations. We may also issue convertible debt securities. Unless otherwise specified in a prospectus supplement, the debt securities will be direct unsecured obligations of the Company.

Any indenture or form of indenture will be filed as an exhibit to the registration statement of which this prospectus is a part. The statements and descriptions in this prospectus or in any prospectus supplement regarding provisions of the indentures and debt securities are summaries thereof, do not purport to be complete and are subject to, and are qualified in their entirety by reference to, all of the provisions of the indentures (and any amendments or supplements we may enter into from time to time that are permitted under each Indenture) and the debt securities, including the definitions in the applicable indenture of various terms.

The indentures might not limit the aggregate principal amount of debt securities that we may issue and may provide that we may issue debt securities from time to time in one or more series, in each case with the same or various maturities, at par or at a discount. Unless indicated in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of the series outstanding at the time of the issuance. Any of the additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of debt securities under the applicable indenture and will be equal in ranking.

Each prospectus supplement will describe the terms relating to the specific series of debt securities being offered. These terms may include some or all of the following:

● the title of the series of the offered debt securities;

● the price or prices at which the offered debt securities will be issued;

● any limit on the aggregate principal amount of the offered debt securities;

● the date or dates on which the principal of the offered debt securities will be payable;

● the rate or rates (which may be fixed or variable) per year at which the offered debt securities will bear interest, if any, or the method of determining the rate or rates and the date or dates from which interest, if any, will accrue;

● if the amount of principal, premium or interest with respect to the offered debt securities of the series may be determined with reference to an index or pursuant to a formula, the manner in which these amounts will be determined;

● the date or dates on which interest, if any, on the offered debt securities will be payable and the regular record dates for the payment thereof;

● the place or places, if any, in addition to or instead of the corporate trust office of the trustee, where the principal, premium, and interest with respect to the offered debt securities will be payable;

● the period or periods, if any, within which, the price or prices of which, and the terms and conditions upon which the offered debt securities may be redeemed, in whole or in part, pursuant to optional redemption provisions;

● the terms on which we would be required to redeem or purchase the offered debt securities pursuant to any sinking fund or similar provision, and the period or periods within which, the price or prices at which and the terms and conditions on which the offered debt securities will be so redeemed and purchased in whole or in part;

● the denominations in which the offered debt securities will be issued;

● the form of the offered debt securities and whether the offered debt securities are to be issued in whole or in part in the form of one or more global securities and, if so, the identity of the depositary for the global security or securities;

● the portion of the principal amount of the offered debt securities that is payable on the declaration of acceleration of the maturity, if other than their principal amount;

● if other than U.S. dollars, the currency or currencies in which the offered debt securities will be denominated and payable, and the holders' rights, if any, to elect payment in a foreign currency or a foreign currency unit other than that in which the offered debt securities are otherwise payable;

● whether the offered debt securities will be issued with guarantees and, if so, the terms of any guarantee of the payment of principal and interest with respect to the offered debt securities;

● any addition to, or modification or deletion of, any event of default or any covenant specified in the indenture;

● whether the offered debt securities will be convertible or exchangeable into other securities, and if so, the terms and conditions upon which the offered debt securities will be convertible or exchangeable;

● whether the offered debt securities will be senior or subordinated debt securities;

● whether the offered debt securities will be secured or unsecured, and the terms of any secured debt;

● any trustees, authenticating or paying agents, transfer agents, or registrars or other agents with respect to the offered debt securities; and

● any other specific terms of the offered debt securities.

Unless otherwise specified in the applicable prospectus supplement, the debt securities will not be listed on any securities exchange and will be issued in fully-registered form without coupons.

The applicable prospectus supplement may contain information as to how we will determine the amount of principal or interest payable on any date, as well as the currencies, commodities, equity indices or other factors to which the amount payable on that date relates and various additional tax considerations.

**PLAN OF DISTRIBUTION**

We are registering the securities covered by this prospectus on our behalf. All costs, expenses and fees connected with the registration of such securities will be borne by us. Any brokerage commissions and similar expenses connected with selling such shares of Common Stock will be borne by the Company, according to the allocation of shares sold. We may offer and sell such securities and shares of Common Stock from time to time in one or more transactions. These transactions include the following methods of sale:

● at a fixed price or prices, which may be changed;

● at market prices prevailing at the time of sale;

● at prices related to such prevailing market prices; or

● at negotiated prices.

Each time that we sell securities covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms and conditions of the offering of such securities, including the offering price of the securities and the proceeds to us, if applicable.

Offers to purchase the securities being offered by this prospectus may be solicited directly. Agents may also be designated to solicit offers to purchase the securities from time to time. Any agent involved in the offer or sale of our securities will be identified in a prospectus supplement.

If a dealer is utilized in the sale of the securities being offered by this prospectus, the securities will be sold to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

If an underwriter is utilized in the sale of the securities being offered by this prospectus, an underwriting agreement will be executed with the underwriter at the time of sale and the name of any underwriter will be provided in the prospectus supplement that the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions, or commissions from the underwriters and/or commissions from the purchasers for which they may act as agent. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and may then resell the securities at varying prices to be determined by the dealer.

Any compensation paid to underwriters, dealers, or agents in connection with the offering of the securities, and any discounts, concessions, or commissions allowed by underwriters to participating dealers will be provided in the applicable prospectus supplement. Underwriters, dealers, and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act, and any discounts and commissions received by them, and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers, and agents against civil liabilities, including liabilities under the Securities Act, or to contribute to payments they may be required to make in respect thereof and to reimburse those persons for certain expenses.

Agents who may become involved in the sale of securities covered by this prospectus may engage in transactions with, and perform other services for, us in the ordinary course of their business for which they receive compensation.

Any Common Stock will be listed on the NYSE American, but any other securities may or may not be listed on a national securities exchange. To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securities than were sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option, if any. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act.

In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

We do not make any representation or prediction as to the direction or magnitude of any effect that the transactions described above might have on the price of the securities. In addition, we do not make any representation that underwriters will engage in such transactions or that such transactions, once commenced, will not be discontinued without notice.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

To comply with applicable state securities laws, the securities offered by this prospectus will be sold, if necessary, in such jurisdictions only through registered or licensed brokers or dealers. In addition, securities may not be sold in some states unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

The underwriters, dealers, and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

**LEGAL MATTERS**

Unless otherwise indicated in the applicable prospectus supplement, the validity of the securities offered by this prospectus will be passed upon for us by Lucosky Brookman LLP, Woodbridge, New Jersey. If legal matters in connection with offerings made by this prospectus are passed on by counsel for the underwriters, dealers, or agents, if any, that counsel will be named in the applicable prospectus supplement.

**EXPERTS**

Our consolidated financial statements as of December 31, 2023 and 2022 and for each of the years in the two-year period ended December 31, 2023 incorporated in this Prospectus by reference from the Company's Annual Report on From 10-K for the year ended December 31, 2023 have been audited by RSM US LLP, an independent registered public accounting firm, as stated in their reports thereon, incorporated herein by reference, and have been incorporated in this Prospectus and Registration Statement in reliance upon such report and upon the authority of such firm as experts in accounting and auditing.

**EXPLANATORY NOTE**

Castellum, Inc. is filing this Pre-Effective Amendment No. 1 ("Amendment No. 1") to its Registration Statement on Form S-3 (File No. 333-284205), originally filed on January 10, 2025 (the "Registration Statement"), solely to file Exhibit 4.4 – Form of Indenture relating to the issuance from time to time in one or more series of debentures, notes, bonds, or other evidences of indebtedness, and Exhibit 25.1- Form T-1, to be filed separately pursuant to Section 305(b)(2) of the Trust Indenture Act of 1939 . No changes are being made to Part I of the Registration Statement. Accordingly, this Amendment No. 1 consists only of the facing page, this explanatory note, Part II of the Registration Statement, the signature page to the Registration Statement, and the exhibits being filed with this Amendment No. 1. The remainder of the Registration Statement, including the prospectus, is unchanged and has been omitted.

**Castellum, Inc.**

**Units consisting of Shares of Common Stock and Warrants to purchase up to Shares of Common Stock**

**PROSPECTUS SUPPLEMENT**

Maxim Group LLC

**June , 2025**