Castellum, Inc.
CTM- Exchange
- NYSE
- Industry
- Services-Management Consulting Services
- SEC CIK
- 0001877939
In the last 90 days, Castellum, Inc. insiders filed 5 open-market purchases and 0 sales; 35 institutions reported holding it in 13F filings for Q2 2026, worth $5.69M in total; no superinvestor holds it.
Q1 2026 vs. Q4 2025
How the institutions holding Castellum, Inc. changed between Q4 2025 and Q1 2026.
All holders in Q1 2026All holders in Q4 2025
| Measure | Q4 2025 | Of which not filed for Q1 2026 | Q1 2026 | Change |
|---|---|---|---|---|
| Holders | 40 | 2 | 27 | −11 |
| Shares | 13.0M | 3.49M | 7.74M | −1.77M (−18.6%) |
| Value | $11.7M | $3.15M | $4.56M | −$4.02M (−46.9%) |
2 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so the changes leave them out.
New holders (8)
Institutions that held Castellum, Inc. at the end of Q1 2026 but not at the end of Q4 2025.
| Institution | Shares | Value | % of portfolio |
|---|---|---|---|
| Vanguard Capital Management LLC | 3,081,257 | $1.82M | 0.00% |
| Captrust Financial Advisors | 626,100 | $369.1K | 0.00% |
| Vanguard Fiduciary Trust Co | 418,324 | $246.8K | 0.00% |
| HRT Financial LP | 33,836 | $19.0K | 0.00% |
| Vanguard Global Advisers, LLC | 27,344 | $16.1K | 0.00% |
| Capital Advisors Inc | 22,000 | $13.0K | 0.00% |
| Ground Swell Capital, LLC | 21,090 | $12.4K | 0.02% |
| Two Sigma Securities, LLC | 15,222 | $8.97K | 0.00% |
Sold out (19)
Institutions that held Castellum, Inc. at the end of Q4 2025 and filed for Q1 2026 without it.
| Institution | Shares, Q4 2025 | Value, Q4 2025 |
|---|---|---|
| Essex Investment Management Co LLC | 2,114,029 | $1.91M |
| Legato Capital Management LLC | 680,945 | $615.0K |
| Goldman Sachs Group Inc | 353,526 | $319.3K |
| Quadrature Capital Ltd | 217,471 | $196.4K |
| Susquehanna International Group, LLP | 102,556 | $92.6K |
| Bank of New York Mellon Corp | 100,002 | $90.3K |
| Two Sigma Investments, LP | 75,384 | $68.1K |
| Inspire Advisors, LLC | 41,700 | $37.7K |
| Point72 Asset Management, L.P. | 34,668 | $31.3K |
| Squarepoint Ops LLC | 26,781 | $24.2K |
| Royal Bank of Canada | 22,000 | $20.0K |
| Centiva Capital, LP | 19,409 | $17.5K |
| PKS Advisory Services, LLC | 18,931 | $17.1K |
| Virtu Financial LLC | 16,804 | $15.0K |
| Revisor Wealth Management LLC | 12,922 | $12.3K |
| Independent Advisor Alliance | 12,835 | $11.6K |
| Strengthening Families & Communities, LLC | 3,000 | $2.71K |
| Tower Research Capital LLC (TRC) | 2,973 | $2.69K |
| Bank of America Corp | 866 | $782 |
Not filed for Q1 2026 yet (2)
Institutions that held Castellum, Inc. at the end of Q4 2025 and haven't filed a 13F for Q1 2026. Not filing isn't selling, so they aren't counted as sold out.
| Institution | Shares, Q4 2025 | Value, Q4 2025 |
|---|---|---|
| Vanguard Group Inc | 3,473,227 | $3.14M |
| Global Retirement Partners, LLC | 16,439 | $14.8K |