# EDGAR Filing Document

**Accession Number:** 0001877939
**File Stem:** 0001877939-26-000005
**Filing Date:** 2026-1
**Character Count:** 5013
**Document Hash:** 4249d0038bc225b8222e38d072793f5e
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001877939-26-000005.hdr.sgml**: 20260102

**ACCESSION NUMBER**: 0001877939-26-000005

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260101

**FILED AS OF DATE**: 20260102

**DATE AS OF CHANGE**: 20260102

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** MARTIN TAMMY L
- **CENTRAL INDEX KEY:** 0001329293

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41526
- **FILM NUMBER:** 26502326

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

**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

**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

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

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>MARTIN TAMMY L<br><sub>(Last) (First) (Middle)</sub><br>1934 OLD GALLOWS ROAD, SUITE 350<br><sub>(Street)</sub><br>VIENNA, VA 22182<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>Castellum, Inc. [ CTM ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2026-01-01 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [ ] 10% Owner<br>[X] Officer (give title below)   [ ] Other (specify below)<br>_General Counsel  and Secretary_ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |
| Common Stock | 12500 | D |  |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| Stock Options | 2023-01-01<sup>(1)</sup> | 2029-10-16 | Common Stock | 12500 | $2 | D |  |
| Stock Options | <sup>(2)</sup> | 2032-01-21 | Common Stock | 100000 | $1.07 | D |  |
| Stock Options | <sup>(3)</sup> | 2032-11-10 | Common Stock | 175000 | $1.19 | D |  |

---

### Footnotes:

(1) Ms. Martin holds a total of 12, 500 stock options to purchase 12,500 shares of Common Stock, all of which are exercisable.

(2) Ms. Martin holds a total of 100,000 stock options to purchase 100,000 shares of Common Stock, 50,000 of which vest ratably over thirty-six months commencing February 1, 2025 and 50,000  of which vest ratably over thirty-six months commencing March 1, 2025.

(3) Ms. Martin holds a total of 175,000 stock options to purchase 175,000 shares of Common Stock, which vest ratably over twenty months commencing December 1, 2025.

**Signature:** /s/ Tammy L. Martin  
**Date:** 2026-01-02

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**