Geospace Technologies Corp
GEOS- Exchange
- Nasdaq
- Industry
- Measuring & Controlling Devices, NEC
- SEC CIK
- 0001001115
No open-market purchases or sales by Geospace Technologies Corp insiders were filed in the last 90 days; 82 institutions reported holding it in 13F filings for Q2 2026, worth $34.9M in total; no superinvestor holds it.
Holders of 5% or more of GEOS
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Geospace Technologies Corp, largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| Disciplined Growth Investors Inc | 13G/A | 8.80%1.13M shares | −0.20 ppfrom 9.00% | Nov 14, 20246 filings | Feb 17, 2026 | SEC |
| Tieton Capital Management, LLC | 13G/A | 6.90%885.7K shares | – | Feb 11, 20251 filing | Feb 11, 2025 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
12 Schedule 13D and 13G filings on Geospace Technologies Corp, newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Mar 26, 20266:35 PM ET | Vanguard Group Inc | 13G/A | 0.00%0 shares | −4.94 ppfrom 4.94%Below 5% | Mar 13, 2026 | SEC |
| Feb 17, 20264:32 PM ET | Disciplined Growth Investors Inc | 13G/A | 8.80%1.13M shares | −0.20 ppfrom 9.00% | Dec 31, 2025 | SEC |
| Nov 14, 20253:50 PM ET | Disciplined Growth Investors Inc | 13G/A | 9.00%1.15M shares | −0.70 ppfrom 9.70% | Sep 30, 2025 | SEC |
| Oct 30, 20253:19 PM ET | Vanguard Group Inc | 13G/A | 4.94%634.5K shares | –Below 5% | Sep 30, 2025 | SEC |
| Oct 9, 20251:48 PM ET | Dimensional Fund Advisors LP | 13G/A | 4.90%628.4K shares | −0.20 ppfrom 5.10%Below 5% | Sep 30, 2025 | SEC |
| Aug 14, 20257:20 PM ET | Disciplined Growth Investors Inc | 13G/A | 9.70%1.24M shares | −0.20 ppfrom 9.90% | Jun 30, 2025 | SEC |
| Jul 17, 20257:54 PM ET | BlackRock, Inc. | 13G/A | 2.70%341.6K shares | –Below 5% | Jun 30, 2025 | SEC |
| May 15, 20254:15 PM ET | Disciplined Growth Investors Inc | 13G/A | 9.90%1.27M shares | −1.30 ppfrom 11.20% | Mar 31, 2025 | SEC |
| Feb 14, 20252:59 PM ET | Disciplined Growth Investors Inc | 13G/A | 11.20%1.43M shares | −0.90 ppfrom 12.10% | Dec 31, 2024 | SEC |
| Feb 11, 202511:44 AM ET | Tieton Capital Management, LLC | 13G/A | 6.90%885.7K shares | – | Dec 31, 2024 | SEC |
| Jan 23, 20253:55 PM ET | Dimensional Fund Advisors LP | 13G | 5.10%649.9K shares | New | Dec 31, 2024 | SEC |
| Nov 14, 20244:24 PM ET | Disciplined Growth Investors Inc | 13G/A | 12.10%1.56M shares | – | Sep 30, 2024 | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Geospace Technologies Corp shares.
No Form 144 notices for Geospace Technologies Corp are on file.