Tetra Tech, Inc.
US ˙ NasdaqGS ˙ US88162G1031

SecurityTTEK / Tetra Tech, Inc.
InstitutionOak Thistle LLC
Latest Disclosed Ownership117,586 shares
Latest Disclosed Value $ 3,541,691
Oak Thistle LLC ownership in TTEK / Tetra Tech, Inc.

On April 10, 2026 - Oak Thistle LLC filed a 13F-HR form disclosing ownership of 117,586 shares of Tetra Tech, Inc. (US:TTEK) valued at $3,541,690 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 21, 2026 disclosing 0 shares of Tetra Tech, Inc.. The current value of the position is $3,288,880 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-04-10 2026-03-31 13F TETRA TECH INC COM 88162G103 117,586 117,586 3,542 0.3438
2026-01-21 2025-12-31 13F TETRA TECH INC COM 88162G103 0 -35,899 -100.00 0 -100.00
2025-10-07 2025-09-30 13F TETRA TECH INC COM 88162G103 35,899 2,931 8.89 1,198 1.10 0.1827
2025-08-08 2025-06-30 13F TETRA TECH INC COM 88162G103 32,968 13,540 69.69 1,186 108.63 0.1746
2025-05-06 2025-03-31 13F TETRA TECH INC COM 88162G103 19,428 -595 -2.97 568 -28.73 0.1144
2025-01-14 2024-12-31 13F TETRA TECH INC COM 88162G103 20,023 -23,292 -53.77 798 -60.97 0.2369
2024-11-12 2024-09-30 13F TETRA TECH INC COM 88162G103 43,315 43,315 2,043 0.6641
2024-01-22 2023-12-31 13F TETRA TECH INC COM 88162G103 0 -1,401 -100.00 0 -100.00
2023-10-18 2023-09-30 13F TETRA TECH INC COM 88162G103 1,401 1,401 213 0.0629
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.