Reported relationships
Latest disclosed role at each company.
No relationships currently tracked through insider filings.
Disclosed balances
About these balances
Latest available filing per company, not a reconstructed current portfolio. Matching sequences show the last reported balance with all source rows expandable; grouping alone does not establish account ownership. Do not add unresolved positions together. Filings may omit unchanged positions, and amendments may correct only part of an older disclosure. Jointly reported shares are not necessarily this owner's personal holdings.
No balances currently tracked through insider filings.
Past disclosures · reporting ended (1)
No longer tracked through insider filings. These historical balances do not imply present ownership or a zero position.
Castellum, Inc.
Report date September 03, 2025 · Filed September 03, 2025
Section 16 reporting ended · disclosed 2025-09-03. Current position is not established by this disclosure.
| Security / award | Ownership account | Disclosed shares / units | Disclosure context |
|---|---|---|---|
| Common StockSEC Table I · non-derivative | Direct | 6,113,659 |
Reported balance
After 2025-09-03 transaction · row 1
Account or security details depend on footnotes; rows are not merged.
1 source rowRow 1 · 2025-09-03 · Sale · Disposed 500,000 · Balance 6,113,659 F1: Includes (a) 6,047,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 common shares held by Mark Fuller. F2: Effective May 28, 2025, Mr. Fuller ceased to be a member of the Company's board of directors. F3: Effective June 12, 2025, Mr. Fuller ceased to be an affiliate of the Company. |
Filing footnotes · ownership attribution and instrument terms
F1: Includes (a) 6,047,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 common shares held by Mark Fuller.
F2: Effective May 28, 2025, Mr. Fuller ceased to be a member of the Company's board of directors.
F3: Effective June 12, 2025, Mr. Fuller ceased to be an affiliate of the Company.
Transaction history
JSON APIPurchases/sales include open-market and private transactions. Plan disclosure applies to the filing; individual rows may differ. “Not disclosed” is not “unplanned.”
The cutoff filters transaction history only. Company summaries and owner relationships show the latest available disclosures. Parser corrections can improve historical records.
| Transaction date | Company | Activity / security | Shares / units | Reported price | Reported value | Details |
|---|---|---|---|---|---|---|
| September 03, 2025 Filed Sep 3, 2025 21:06 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 500,000 | $1.12 | $560,000.00 |
DisclosureSEC source: 0001944544-25-000014 · wk-form4_1756933593.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Former Officer and Affiliate 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 6,113,659 F1 · balance_after: Includes (a) 6,047,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 common shares held by Mark Fuller. F2 · balance_after: Effective May 28, 2025, Mr. Fuller ceased to be a member of the Company's board of directors. F3 · balance_after: Effective June 12, 2025, Mr. Fuller ceased to be an affiliate of the Company. Read SEC document |
| May 19, 2025 Filed May 20, 2025 20:50 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 500,000 | $1.05 | $524,000.00 |
DisclosureSEC source: 0001944544-25-000012 · wk-form4_1747774252.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 6,613,659 F1 · balance_after: Includes (a) 6,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (e) 16,140 common shares held by Mark Fuller. Read SEC document |
| March 06, 2025 Filed Mar 6, 2025 22:03 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 225,000 | $1.33 | $299,700.00 |
DisclosureSEC source: 0001944544-25-000010 · wk-form4_1741298609.xml · nonDerivative · entry 3 Fuller Mark C · CIK 0001944544 · Director · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 7,113,659 F4 · balance_after: Includes (a) 7,047,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 common shares held by Mark Fuller. Read SEC document |
| March 05, 2025 Filed Mar 6, 2025 22:03 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 275,000 | $1.49 | $410,575.00 |
DisclosureSEC source: 0001944544-25-000010 · wk-form4_1741298609.xml · nonDerivative · entry 2 Fuller Mark C · CIK 0001944544 · Director · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 7,338,659 F3 · balance_after: Includes (a) 7,272,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 common shares held by Mark C. Fuller. Read SEC document |
| March 05, 2025 Filed Mar 6, 2025 22:03 UTC | Castellum, Inc. CTM · Entity 7164 | OtherCommon Stock | 50,000 | Not disclosed | Not disclosed |
DisclosureSEC source: 0001944544-25-000010 · wk-form4_1741298609.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 7,613,659 F1 · price: Removes 50,000 shares of common stock previously reported on Form 4 on June 14, 2023 which is owned by Reporting Person's children who are now adults. F2 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, and (c) 16,140 shares held by Mark C. Fuller. Read SEC document |
| June 13, 2023 Filed Jun 14, 2023 10:01 UTC | Castellum, Inc. CTM · Entity 7164 | PurchaseCommon Stock | 1,000 | $0.65 | $649.50 |
DisclosureSEC source: 0001575872-23-000955 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · CEO, President · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 7,663,659 F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 16,140 common shares held by Mark Fuller. Read SEC document |
| March 22, 2023 Filed Mar 24, 2023 20:16 UTC | Castellum, Inc. CTM · Entity 7164 | GrantWarrants · Derivative | 532,931 | Not disclosed Strike: $1.04 | Not disclosed |
DisclosureSEC source: 0001575872-23-000437 · ownership.xml · derivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · CEO, President · 10% owner 10b5-1 filing: No plan indicated Ownership: Direct Disclosed balance after: 532,931 Underlying: Common Stock · 532,931 shares Expires 2030-03-21 F1 · price: Pursuant to the terms of his employment agreement and in connection with the closing of the Agreement and Plan of Merger with Global Technology and Management Resources, Inc., Mr. Fuller received 532,931 warrants to purchase 532,931 shares of common stock at $1.04 per share, all of which are exercisable. Read SEC document |
| December 02, 2022 Filed Dec 9, 2022 20:48 UTC | Castellum, Inc. CTM · Entity 7164 | PurchaseCommon Stock | 1,294 | $1,246.00 | $1,612,324.00 |
DisclosureSEC source: 0001575872-22-001296 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 7,662,659 F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 15,140 common shares held by Mark Fuller. Read SEC document |
| November 30, 2022 Filed Dec 1, 2022 11:06 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 9,544 | $8,017.00 | $76,514,248.00 |
DisclosureSEC source: 0001575872-22-001203 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 7,661,365 F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 13,846 common shares held by Mark Fuller. Read SEC document |
| November 30, 2022 Filed Dec 2, 2022 22:32 UTC Amendment | Castellum, Inc. CTM · Entity 7164 | PurchaseCommon Stock | 9,544 | $8,017.00 | $76,514,248.00 |
DisclosureSEC source: 0001575872-22-001226 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 7,661,365 F2 · kind: This amendment to Form 4 is filed to accurately reflect the transactions as a purchase (P) in column 3. F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 13,846 common shares held by Mark Fuller. Read SEC document |
| November 28, 2022 Filed Nov 30, 2022 11:57 UTC | Castellum, Inc. CTM · Entity 7164 | SaleCommon Stock | 4,302 | $2,860.00 | $12,303,720.00 |
DisclosureSEC source: 0001575872-22-001192 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 7,651,821 F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 4,302 common shares held by Mark Fuller. Read SEC document |
| November 28, 2022 Filed Dec 2, 2022 22:34 UTC Amendment | Castellum, Inc. CTM · Entity 7164 | PurchaseCommon Stock | 4,302 | $2,860.00 | $12,303,720.00 |
DisclosureSEC source: 0001575872-22-001228 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 7,651,821 F2 · kind: This amendment to Form 4 is filed to accurately reflect the transactions as a purchase (P) in column 3. F1 · balance_after: Includes (a) 7,547,519 common shares held by The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE, (b) 50,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 25,000 common shares held by Michael Fuller, and (e) 4,302 common shares held by Mark Fuller. Read SEC document |
| October 17, 2022 Filed Oct 20, 2022 17:22 UTC | Castellum, Inc. CTM · Entity 7164 | GrantWarrants · Derivative | 500,000 | Not disclosed Strike: $2.00 | Not disclosed |
DisclosureSEC source: 0001575872-22-000997 · ownership.xml · derivative · entry 3 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Direct Disclosed balance after: 500,000 Underlying: Common Stock · 500,000 shares Expires 2029-10-16 F2 · price: Pursuant to the terms of his employment agreement, Mr. Fuller was granted warrants to purchase 500,000 warrants to purchase Common Stock at $2.00 per share in connection with the Company's offering, all of which are excercisable. Read SEC document |
| October 17, 2022 Filed Oct 20, 2022 17:22 UTC | Castellum, Inc. CTM · Entity 7164 | ConversionSeries B Preferred Stock · Derivative | 1,504,500 | Not disclosed | Not disclosed |
DisclosureSEC source: 0001575872-22-000997 · ownership.xml · derivative · entry 2 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Indirect · See footnote Disclosed balance after: 0 Underlying: Common Stock · 7,522,500 shares Expires not disclosed Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event. F1 · derivative.exercise_price: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. F1 · price: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. F1 · derivative.exercise_date: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. F1 · derivative.expiration_date: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. F1 · ownership.nature: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. Read SEC document |
| October 17, 2022 Filed Oct 20, 2022 17:22 UTC | Castellum, Inc. CTM · Entity 7164 | ConversionCommon Stock | 7,522,500 | Not disclosed | Not disclosed |
DisclosureSEC source: 0001575872-22-000997 · ownership.xml · nonDerivative · entry 1 Fuller Mark C · CIK 0001944544 · Director · Chief Executive Officer · 10% owner 10b5-1 filing: Not disclosed Ownership: Indirect · See footnote Disclosed balance after: 8,863,453 Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event. F1 · price: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. F1 · ownership.nature: The Mark Chappelle Fuller Revocable Trust, Mark Fuller, TTEE held 1,504,500 shares of Series B Preferred Stock which was converted into 7,522,500 shares of Common Stock. Includes (a) 7,447,519 common shares held by The Mark Chappelle Fuller Reocable Trust, Mark Fuller, TTEE, (b) 25,000 common shares held by Janice Lynn Dudley Revocable Trust, Janice Lynn Dudley TTEE, (c) 25,000 common shares held by Katherine Fuller, (d) 50,000 common shares held by Michael Fuller. Read SEC document |
Value uses the disclosed total when available, otherwise shares × reported transaction price. It is not an estimate of exercise cash cost or investment performance.