Tetra Tech, Inc.
US ˙ NasdaqGS ˙ US88162G1031

SecurityTTEK / Tetra Tech, Inc.
InstitutionAsset Management One Co., Ltd.
Latest Disclosed Ownership110,981 shares
Latest Disclosed Value $ 3,342,748
Asset Management One Co., Ltd. reports 13.14% increase in ownership of TTEK / Tetra Tech, Inc.

On May 8, 2026 - Asset Management One Co., Ltd. filed a 13F-HR form disclosing ownership of 110,981 shares of Tetra Tech, Inc. (US:TTEK) valued at $3,342,748 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 27, 2026 disclosing 98,096 shares of Tetra Tech, Inc.. This represents a change in shares of 13.14% during the quarter. The current value of the position is $3,104,139 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)
2026-05-08 2026-03-31 13F TETRA TECH INC COM 88162G103 110,981 12,885 13.14 3,343 -0.12 0.0099
2026-01-27 2025-12-31 13F TETRA TECH INC COM 88162G103 98,096 -81,900 -45.50 3,346 -44.31 0.0093
2025-10-22 2025-09-30 13F TETRA TECH INC COM 88162G103 179,996 -50,432 -21.89 6,008 -27.47 0.0174
2025-07-31 2025-06-30 13F TETRA TECH INC COM 88162G103 230,428 -39,808 -14.73 8,284 4.86 0.0260
2025-04-23 2025-03-31 13F TETRA TECH INC COM 88162G103 270,236 -37,760 -12.26 7,900 -35.59 0.0273
2025-01-30 2024-12-31 13F TETRA TECH INC COM 88162G103 307,996 11,875 4.01 12,266 -11.83 0.0421
2024-10-30 2024-09-30 13F TETRA TECH INC COM 88162G103 296,121 235,866 391.45 13,911 11.56 0.0495
2024-07-18 2024-06-30 13F TETRA TECH INC COM 88162G103 60,255 30,588 103.10 12,471 127.60 0.0477
2024-05-02 2024-03-31 13F TETRA TECH INC COM 88162G103 29,667 -1,016 -3.31 5,480 6.29 0.0211
2024-01-24 2023-12-31 13F TETRA TECH INC COM 88162G103 30,683 -1,012 -3.19 5,156 6.99 0.0208
2023-10-19 2023-09-30 13F TETRA TECH INC COM 88162G103 31,695 180 0.57 4,819 -6.63 0.0215
2023-07-31 2023-06-30 13F TETRA TECH INC COM 88162G103 31,515 -4,444 -12.36 5,160 -2.31 0.0218
2023-04-25 2023-03-31 13F TETRA TECH INC COM 88162G103 35,959 0 0.00 5,283 0.59 0.0239
2023-02-06 2022-12-31 13F TETRA TECH INC COM 88162G103 35,959 -3,525 -8.93 5,252 3.49 0.0256
2022-11-04 2022-09-30 13F TETRA TECH INC COM 88162G103 39,484 -6,040 -13.27 5,074 -18.37 0.0258
2022-07-29 2022-06-30 13F TETRA TECH INC COM 88162G103 45,524 -1,739 -3.68 6,216 -20.26 0.0292
2022-05-13 2022-03-31 13F TETRA TECH INC COM 88162G103 47,263 -7,643 -13.92 7,795 -16.41 0.0304
2022-02-09 2021-12-31 13F TETRA TECH INC COM 88162G103 54,906 0 0.00 9,325 13.73 0.0325
2021-11-02 2021-09-30 13F TETRA TECH INC COM 88162G103 54,906 -13 -0.02 8,199 22.34 0.0314
2021-08-03 2021-06-30 13F TETRA TECH INC COM 88162G103 54,919 14,498 35.87 6,702 22.19 0.0249
2021-05-14 2021-03-31 13F TETRA TECH INC COM 88162G103 40,421 2,224 5.82 5,485 24.26 0.0218
2021-02-12 2020-12-31 13F TETRA TECH INC COM 88162G103 38,197 -5,247 -12.08 4,414 6.39 0.0182
2020-11-13 2020-09-30 13F TETRA TECH INC COM 88162G103 43,444 -3,859 -8.16 4,149 10.85 0.0191
2020-08-14 2020-06-30 13F TETRA TECH INC COM 88162G103 47,303 0 0.00 3,743 12.03 0.0184
2020-05-14 2020-03-31 13F TETRA TECH INC COM 88162G103 47,303 -16,218 -25.53 3,341 -38.95 0.0195
2020-02-14 2019-12-31 13F TETRA TECH INC COM 88162G103 63,521 -14,130 -18.20 5,473 -18.75 0.0247
2019-11-14 2019-09-30 13F TETRA TECH INC COM 88162G103 77,651 -5,369 -6.47 6,736 3.30 0.0324
2019-08-14 2019-06-30 13F TETRA TECH INC COM 88162G103 83,020 -16,728 -16.77 6,521 9.71 0.0320
2019-05-15 2019-03-31 13F TETRA TECH INC COM 88162G103 99,748 2,902 3.00 5,944 19.77 0.0321
2019-02-13 2018-12-31 13F TETRA TECH INC COM 88162G103 96,846 3,847 4.14 4,963 -21.17 0.0118
2018-11-14 2018-09-30 13F TETRA TECH INC COM 88162G103 92,999 -31,542 -25.33 6,296 -12.01 0.0129
2018-08-14 2018-06-30 13F TETRA TECH INC COM 88162G103 124,541 -37,016 -22.91 7,155 -9.52 0.0156
2018-05-14 2018-03-31 13F TETRA TECH INC COM 88162G103 161,557 25,839 19.04 7,908 20.26 0.0178
2018-02-14 2017-12-31 13F TETRA TECH INC COM 88162G103 135,718 0 0.00 6,576 4.88 0.0145
2017-11-14 2017-09-30 13F TETRA TECH INC COM 88162G103 135,718 135,718 6,270 0.0147
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.