Tetra Tech Inc
TTEK- Exchange
- Nasdaq
- Industry
- Services-Engineering Services
- SEC CIK
- 0000831641
No open-market purchases or sales by Tetra Tech Inc insiders were filed in the last 90 days; 555 institutions reported holding it in 13F filings for Q2 2026, worth $7.32B in total; no superinvestor holds it.
Holders of 5% or more of TTEK
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Tetra Tech Inc, largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| BlackRock, Inc. | 13G/A | 9.70%26.0M shares | – | Feb 6, 20251 filing | Feb 6, 2025 | SEC |
| Vanguard Capital Management LLC | 13G | 5.23%13.7M shares | New | Apr 30, 20261 filing | Apr 30, 2026 | 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
9 Schedule 13D and 13G filings on Tetra Tech Inc, newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Apr 30, 20262:01 PM ET | Vanguard Capital Management LLC | 13G | 5.23%13.7M shares | New | Mar 31, 2026 | SEC |
| Mar 27, 20261:33 PM ET | Vanguard Group Inc | 13G/A | 0.00%0 shares | −10.14 ppfrom 10.14%Below 5% | Mar 13, 2026 | SEC |
| Oct 17, 20251:09 PM ET | Pictet Asset Management SA | 13D/A | 4.90%13.0M shares | −0.40 ppfrom 5.30%Below 5% | Oct 16, 2025 | SEC |
| Apr 15, 20252:06 PM ET | Pictet Asset Management SA | 13D/A | 5.30%14.5M shares | +0.10 ppfrom 5.20% | Apr 15, 2025 | SEC |
| Apr 7, 202511:51 AM ET | Vanguard Group Inc | 13G/A | 10.14%27.2M shares | – | Mar 31, 2025 | SEC |
| Feb 11, 20259:44 AM ET | Pictet Asset Management SA | 13G | 5.20%14.0M shares | – | Dec 31, 2024 | SEC |
| Feb 6, 20254:12 PM ET | BlackRock, Inc. | 13G/A | 9.70%26.0M shares | – | Dec 31, 2024 | SEC |
| Feb 10, 2022 | Pictet Asset Management SA | 13GOld format | – | New | – | SEC |
| Feb 10, 2022 | Vanguard Group Inc | 13G/AOld format | – | – | – | SEC |
| Feb 12, 2021 | Dimensional Fund Advisors LP | 13G/AOld format | – | – | – | SEC |
| Feb 10, 2021 | Vanguard Group Inc | 13G/AOld format | – | – | – | SEC |
| Jan 26, 20216:52 PM ET | BlackRock Inc. | 13G/AOld format | – | – | – | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Tetra Tech Inc shares.
No Form 144 notices for Tetra Tech Inc are on file.