Tetra Tech, Inc.
US ˙ NasdaqGS ˙ US88162G1031

SecurityTTEK / Tetra Tech, Inc.
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership1,740,911 shares
Latest Disclosed Value $ 52,436,239
Citadel Advisors Llc ownership in TTEK / Tetra Tech, Inc.

On May 15, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 1,740,911 shares of Tetra Tech, Inc. (US:TTEK) valued at $52,436,239 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 50,593 shares of Tetra Tech, Inc.. This represents a change in shares of 3,341.01% during the quarter. The current value of the position is $48,397,326 USD.

Citadel Advisors Llc has a history of taking positions in derivatives of the underlying security (TTEK) in the form of stock options. The firm currently holds call options representing 17,300 of underlying shares valued at $521,076 USD and put options representing 30,400 of underlying shares valued at $915,648 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

TTEK / Tetra Tech, Inc. Historical Put/Call Ratio
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)
2026-05-15 2026-03-31 13F TETRA TECH INC COM 88162G103 1,740,911 1,690,318 3,341.01 52,436 2,991.75 0.0075
2026-02-17 2025-12-31 13F TETRA TECH INC COM 88162G103 50,593 -948,776 -94.94 1,697 -94.92 0.0003
2025-11-14 2025-09-30 13F TETRA TECH INC COM 88162G103 999,369 -1,874,191 -65.22 33,359 -67.72 0.0051
2025-08-14 2025-06-30 13F TETRA TECH INC COM 88162G103 2,873,560 670,241 30.42 103,333 60.34 0.0179
2025-05-15 2025-03-31 13F TETRA TECH INC COM 88162G103 2,203,319 1,555,533 240.13 64,447 149.73 0.0122
2025-02-14 2024-12-31 13F TETRA TECH INC COM 88162G103 647,786 182,339 39.18 25,808 17.57 0.0045
2024-11-14 2024-09-30 13F TETRA TECH INC COM 88162G103 465,447 300,910 182.88 21,950 -34.76 0.0042
2024-08-14 2024-06-30 13F TETRA TECH INC COM 88162G103 164,537 -18,027 -9.87 33,645 -0.23 0.0068
2024-05-15 2024-03-31 13F TETRA TECH INC COM 88162G103 182,564 -99,552 -35.29 33,721 -28.39 0.0065
2024-02-14 2023-12-31 13F TETRA TECH INC COM 88162G103 282,116 203,957 260.95 47,094 296.34 0.0094
2023-11-14 2023-09-30 13F TETRA TECH INC COM 88162G103 78,159 72,466 1,272.90 11,883 1,174.89 0.0025
2023-08-14 2023-06-30 13F TETRA TECH INC COM 88162G103 5,693 -6,792 -54.40 932 -49.18 0.0002
2023-05-15 2023-03-31 13F TETRA TECH INC COM 88162G103 12,485 -114,708 -90.18 1,834 -90.07 0.0004
2023-02-14 2022-12-31 13F TETRA TECH INC COM 88162G103 127,193 -19,862 -13.51 18,467 -2.30 0.0043
2022-11-14 2022-09-30 13F TETRA TECH INC COM 88162G103 147,055 64,731 78.63 18,901 68.14 0.0043
2022-08-15 2022-06-30 13F TETRA TECH INC COM 88162G103 82,324 62,905 323.94 11,241 250.95 0.0029
2022-05-16 2022-03-31 13F TETRA TECH INC COM 88162G103 19,419 -69,987 -78.28 3,203 -78.90 0.0007
2022-02-14 2021-12-31 13F TETRA TECH INC COM 88162G103 89,406 89,406 15,181 0.0031
2022-03-11 2021-09-30 13F/A-1 TETRA TECH INC COM 88162G103 0 -75,072 -100.00 0 -100.00
2021-11-15 2021-09-30 13F TETRA TECH INC COM 88162G103 0 -75,072 0
2021-08-16 2021-06-30 13F TETRA TECH INC COM 88162G103 75,072 59,037 368.18 9,162 321.05 0.0021
2021-05-21 2021-03-31 13F/A-1 TETRA TECH INC COM 88162G103 16,035 -82,785 -83.77 2,176 -80.98 0.0005
2021-05-17 2021-03-31 13F TETRA TECH INC COM 88162G103 16,035 -82,785 2,176 0.0005
2021-02-16 2020-12-31 13F TETRA TECH INC COM 88162G103 98,820 98,820 11,441 0.0030
2020-08-14 2020-06-30 13F TETRA TECH INC Cmn 88162G103 0 -77,733 -100.00 0 -100.00
2020-05-15 2020-03-31 13F TETRA TECH INC Cmn 88162G103 77,733 24,794 46.84 5,490 20.37 0.0025
2020-02-14 2019-12-31 13F TETRA TECH INC Cmn 88162G103 52,939 48,769 1,169.52 4,561 1,159.94 0.0020
2019-11-14 2019-09-30 13F TETRA TECH INC Cmn 88162G103 4,170 -9,254 -68.94 362 -65.65 0.0002
2019-08-14 2019-06-30 13F TETRA TECH INC Cmn 88162G103 13,424 -77,085 -85.17 1,054 -80.46 0.0005
2019-05-15 2019-03-31 13F TETRA TECH INC Cmn 88162G103 90,509 -8,701 -8.77 5,393 5.00 0.0027
2019-02-14 2018-12-31 13F TETRA TECH INC Cmn 88162G103 99,210 54,976 124.28 5,136 70.01 0.0028
2018-11-13 2018-09-30 13F TETRA TECH INC Cmn 88162G103 44,234 44,234 3,021 0.0014
2018-08-14 2018-06-30 13F/A-1 TETRA TECH INC Cmn 88162G103 0 -16,900 -100.00 0 -100.00
2018-05-14 2018-03-31 13F/A-1 TETRA TECH INC Cmn 88162G103 16,900 6,458 61.85 827 64.41 0.0005
2018-05-11 2018-03-31 13F TETRA TECH INC Cmn 88162G103 16,900 6,458 827
2018-02-09 2017-12-31 13F TETRA TECH INC Cmn 88162G103 10,442 10,442 503 0.0003
2017-02-10 2016-12-31 13F TETRA TECH INC CMN STK Cmn 88162G103 0 -54,516 -100.00 0 -100.00
2017-01-31 2016-09-30 13F/A-1 TETRA TECH INC Cmn 88162G103 54,516 -115,846 -68.00 1,933 -63.10 0.0019
2016-11-10 2016-09-30 13F TETRA TECH INC CMN STK Cmn 88162G103 54,516 -77,177 1,933
2017-01-31 2016-06-30 13F/A-1 TETRA TECH INC Cmn 88162G103 170,362 38,669 29.36 5,238 33.38 0.0058
2016-08-12 2016-06-30 13F TETRA TECH INC CMN STK Cmn 88162G103 170,362 115,846 5,238
2017-01-31 2016-03-31 13F/A-1 TETRA TECH INC Cmn 88162G103 131,693 104,347 381.58 3,927 452.32 0.0050
2016-05-13 2016-03-31 13F TETRA TECH INC CMN STK Cmn 88162G103 131,693 -38,669 3,927
2017-01-31 2015-12-31 13F/A-1 TETRA TECH INC Cmn 88162G103 27,346 2,615 10.57 711 18.30 0.0008
2016-02-12 2015-12-31 13F TETRA TECH INC CMN STK Cmn 88162G103 27,346 -104,347 711
2015-11-16 2015-09-30 13F TETRA TECH INC CMN STK Cmn 88162G103 24,731 22,376 950.15 601 901.67 0.0006
2015-08-14 2015-06-30 13F TETRA TECH INC CMN STK Cmn 88162G103 2,355 -7,391 -75.84 60 -74.36 0.0001
2015-05-15 2015-03-31 13F TETRA TECH INC CMN STK Cmn 88162G103 9,746 -5,681 -36.83 234 -43.20 0.0003
2015-02-17 2014-12-31 13F TETRA TECH INC CMN STK Cmn 88162G103 15,427 -42,825 -73.52 412 -71.68 0.0005
2014-11-14 2014-09-30 13F TETRA TECH INC CMN STK Cmn 88162G103 58,252 -55,790 -48.92 1,455 -53.62 0.0018
2014-08-14 2014-06-30 13F TETRA TECH INC CMN STK Cmn 88162G103 114,042 92,197 422.05 3,137 385.60 0.0042
2014-05-15 2014-03-31 13F TETRA TECH INC CMN STK Cmn 88162G103 21,845 2,803 14.72 646 21.20 0.0009
2014-02-14 2013-12-31 13F TETRA TECH INC CMN STK Cmn 88162G103 19,042 12,722 201.30 533 225.00 0.0007
2013-11-14 2013-09-30 13F TETRA TECH INC CMN STK Cmn 88162G103 6,320 -155,198 -96.09 164 -95.68 0.0003
2013-08-14 2013-06-30 13F TETRA TECH INC CMN STK Cmn 88162G103 161,518 161,518 3,798 0.0066
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F TETRA TECH INC COM Call 17,300 19.31 521 7.20 n/a n/a n/a
2026-02-17 2025-12-31 13F TETRA TECH INC COM Call 14,500 -61.33 486 -61.15 n/a n/a n/a
2025-11-14 2025-09-30 13F TETRA TECH INC COM Call 37,500 -59.98 1,252 -62.87 n/a n/a n/a
2025-08-14 2025-06-30 13F TETRA TECH INC COM Call 93,700 4.23 3,369 28.15 n/a n/a n/a
2025-05-15 2025-03-31 13F TETRA TECH INC COM Call 89,900 70.91 2,630 25.49 n/a n/a n/a
2025-02-14 2024-12-31 13F TETRA TECH INC COM Call 52,600 -55.84 2,096 -62.70 n/a n/a n/a
2024-11-14 2024-09-30 13F TETRA TECH INC COM Call 119,100 215.08 5,617 -27.34 n/a n/a n/a
2024-08-14 2024-06-30 13F TETRA TECH INC COM Call 37,800 98.95 7,729 120.26 n/a n/a n/a
2024-05-15 2024-03-31 13F TETRA TECH INC COM Call 19,000 -69.35 3,509 -66.09 n/a n/a n/a
2024-02-14 2023-12-31 13F TETRA TECH INC COM Call 62,000 196.65 10,350 225.75 n/a n/a n/a
2023-11-14 2023-09-30 13F TETRA TECH INC COM Call 20,900 148.81 3,177 131.05 n/a n/a n/a
2023-08-14 2023-06-30 13F TETRA TECH INC COM Call 8,400 -28.21 1,375 -19.97 n/a n/a n/a
2023-05-15 2023-03-31 13F TETRA TECH INC COM Call 11,700 77.27 1,719 79.33 n/a n/a n/a
2023-02-14 2022-12-31 13F TETRA TECH INC COM Call 6,600 -54.48 958 -48.61 n/a n/a n/a
2022-11-14 2022-09-30 13F TETRA TECH INC COM Call 14,500 16.94 1,864 10.10 n/a n/a n/a
2022-08-15 2022-06-30 13F TETRA TECH INC COM Call 12,400 -29.14 1,693 -41.34 n/a n/a n/a
2022-05-16 2022-03-31 13F TETRA TECH INC COM Call 17,500 -27.98 2,886 -30.05 n/a n/a n/a
2022-02-14 2021-12-31 13F TETRA TECH INC COM Call 24,300 -12.27 4,126 -0.27 n/a n/a n/a
2021-11-15 2021-09-30 13F TETRA TECH INC Cmn Call 27,700 103.68 4,137 149.22 n/a n/a n/a
2021-08-16 2021-06-30 13F TETRA TECH INC COM Call 13,600 -18.07 1,660 -26.32 n/a n/a n/a
2021-05-21 2021-03-31 13F/A TETRA TECH INC COM Call 16,600 -27.19 2,253 -14.66 n/a n/a n/a
2021-05-17 2021-03-31 13F TETRA TECH INC COM Call 16,600 2,253 n/a n/a n/a
2021-02-16 2020-12-31 13F TETRA TECH INC COM Call 22,800 39.02 2,640 68.58 n/a n/a n/a
2020-11-16 2020-09-30 13F TETRA TECH INC COM Call 16,400 -20.39 1,566 -3.93 n/a n/a n/a
2020-08-14 2020-06-30 13F TETRA TECH INC Cmn Call 20,600 -42.46 1,630 -35.52 n/a n/a n/a
2020-05-15 2020-03-31 13F TETRA TECH INC Cmn Call 35,800 72.95 2,528 41.70 n/a n/a n/a
2020-02-14 2019-12-31 13F TETRA TECH INC Cmn Call 20,700 -6.76 1,784 -7.37 n/a n/a n/a
2019-11-14 2019-09-30 13F TETRA TECH INC Cmn Call 22,200 1.37 1,926 11.98 n/a n/a n/a
2019-08-14 2019-06-30 13F TETRA TECH INC Cmn Call 21,900 184.42 1,720 274.73 n/a n/a n/a
2019-05-15 2019-03-31 13F TETRA TECH INC Cmn Call 7,700 459 n/a n/a n/a
2019-02-14 2018-12-31 13F TETRA TECH INC Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2018-11-13 2018-09-30 13F TETRA TECH INC Cmn Call 10,400 48.57 710 73.17 n/a n/a n/a
2018-08-14 2018-06-30 13F/A TETRA TECH INC Cmn Call 7,000 410 n/a n/a n/a
2018-08-10 2018-06-30 13F TETRA TECH INC Cmn Call 7,000 410 n/a n/a n/a
2017-11-09 2017-09-30 13F TETRA TECH INC Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2017-08-11 2017-06-30 13F TETRA TECH INC Cmn Call 5,200 238 n/a n/a n/a
2016-05-13 2016-03-31 13F TETRA TECH INC CMN STK Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2017-01-31 2015-12-31 13F/A TETRA TECH INC Cmn Call 2,500 25.00 65 32.65 n/a n/a n/a
2016-02-12 2015-12-31 13F TETRA TECH INC CMN STK Cmn Call 2,500 65 n/a n/a n/a
2015-11-16 2015-09-30 13F TETRA TECH INC CMN STK Cmn Call 2,000 -33.33 49 -36.36 n/a n/a n/a
2015-08-14 2015-06-30 13F TETRA TECH INC CMN STK Cmn Call 3,000 233.33 77 250.00 n/a n/a n/a
2015-05-15 2015-03-31 13F TETRA TECH INC CMN STK Cmn Call 900 22 n/a n/a n/a
2014-11-14 2014-09-30 13F TETRA TECH INC CMN STK Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2014-08-14 2014-06-30 13F TETRA TECH INC CMN STK Cmn Call 700 600.00 19 533.33 n/a n/a n/a
2014-05-15 2014-03-31 13F TETRA TECH INC CMN STK Cmn Call 100 -94.44 3 -94.00 n/a n/a n/a
2014-02-14 2013-12-31 13F TETRA TECH INC CMN STK Cmn Call 1,800 0.00 50 6.38 n/a n/a n/a
2013-11-14 2013-09-30 13F TETRA TECH INC CMN STK Cmn Call 1,800 -28.00 47 -20.34 n/a n/a n/a
2013-08-14 2013-06-30 13F TETRA TECH INC CMN STK Cmn Call 2,500 59 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F TETRA TECH INC COM Put 30,400 46.86 916 31.84 n/a n/a n/a
2026-02-17 2025-12-31 13F TETRA TECH INC COM Put 20,700 -74.03 694 -73.91 n/a n/a n/a
2025-11-14 2025-09-30 13F TETRA TECH INC COM Put 79,700 -43.23 2,660 -47.31 n/a n/a n/a
2025-08-14 2025-06-30 13F TETRA TECH INC COM Put 140,400 -36.44 5,049 -21.87 n/a n/a n/a
2025-05-15 2025-03-31 13F TETRA TECH INC COM Put 220,900 1,062.63 6,461 754.63 n/a n/a n/a
2025-02-14 2024-12-31 13F TETRA TECH INC COM Put 19,000 80.95 757 52.73 n/a n/a n/a
2024-11-14 2024-09-30 13F TETRA TECH INC COM Put 10,500 1,212.50 495 203.68 n/a n/a n/a
2024-08-14 2024-06-30 13F TETRA TECH INC COM Put 800 -80.00 164 -77.91 n/a n/a n/a
2024-05-15 2024-03-31 13F TETRA TECH INC COM Put 4,000 -52.94 739 -47.95 n/a n/a n/a
2024-02-14 2023-12-31 13F TETRA TECH INC COM Put 8,500 54.55 1,419 69.62 n/a n/a n/a
2023-11-14 2023-09-30 13F TETRA TECH INC COM Put 5,500 89.66 836 76.37 n/a n/a n/a
2023-08-14 2023-06-30 13F TETRA TECH INC COM Put 2,900 20.83 475 34.66 n/a n/a n/a
2023-05-15 2023-03-31 13F TETRA TECH INC COM Put 2,400 84.62 353 87.23 n/a n/a n/a
2023-02-14 2022-12-31 13F TETRA TECH INC COM Put 1,300 189 n/a n/a n/a
2022-11-14 2022-09-30 13F TETRA TECH INC COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2022-08-15 2022-06-30 13F TETRA TECH INC COM Put 3,600 -53.25 492 -61.26 n/a n/a n/a
2022-05-16 2022-03-31 13F TETRA TECH INC COM Put 7,700 266.67 1,270 255.74 n/a n/a n/a
2022-02-14 2021-12-31 13F TETRA TECH INC COM Put 2,100 -70.83 357 -66.79 n/a n/a n/a
2021-11-15 2021-09-30 13F TETRA TECH INC Cmn Put 7,200 -33.94 1,075 -19.17 n/a n/a n/a
2021-08-16 2021-06-30 13F TETRA TECH INC COM Put 10,900 49.32 1,330 34.21 n/a n/a n/a
2021-05-21 2021-03-31 13F/A TETRA TECH INC COM Put 7,300 991 n/a n/a n/a
2021-05-17 2021-03-31 13F TETRA TECH INC COM Put 7,300 991 n/a n/a n/a
2021-02-16 2020-12-31 13F TETRA TECH INC COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2020-11-16 2020-09-30 13F TETRA TECH INC COM Put 3,300 -2.94 315 17.10 n/a n/a n/a
2020-08-14 2020-06-30 13F TETRA TECH INC Cmn Put 3,400 -15.00 269 -4.61 n/a n/a n/a
2020-05-15 2020-03-31 13F TETRA TECH INC Cmn Put 4,000 60.00 282 31.16 n/a n/a n/a
2020-02-14 2019-12-31 13F TETRA TECH INC Cmn Put 2,500 -19.35 215 -20.07 n/a n/a n/a
2019-11-14 2019-09-30 13F TETRA TECH INC Cmn Put 3,100 269 n/a n/a n/a
2019-08-14 2019-06-30 13F TETRA TECH INC Cmn Put 0 -100.00 0 -100.00 n/a n/a n/a
2019-05-15 2019-03-31 13F TETRA TECH INC Cmn Put 17,700 331.71 1,055 397.64 n/a n/a n/a
2019-02-14 2018-12-31 13F TETRA TECH INC Cmn Put 4,100 212 n/a n/a n/a
2015-11-16 2015-09-30 13F TETRA TECH INC CMN STK Cmn Put 0 -100.00 0 -100.00 n/a n/a n/a
2015-08-14 2015-06-30 13F TETRA TECH INC CMN STK Cmn Put 5,100 104.00 131 118.33 n/a n/a n/a
2015-05-15 2015-03-31 13F TETRA TECH INC CMN STK Cmn Put 2,500 60 n/a n/a n/a
2015-02-17 2014-12-31 13F TETRA TECH INC CMN STK Cmn Put 0 -100.00 0 -100.00 n/a n/a n/a
2014-11-14 2014-09-30 13F TETRA TECH INC CMN STK Cmn Put 800 20 n/a n/a n/a
2014-08-14 2014-06-30 13F TETRA TECH INC CMN STK Cmn Put 0 -100.00 0 -100.00 n/a n/a n/a
2014-05-15 2014-03-31 13F TETRA TECH INC CMN STK Cmn Put 900 0.00 27 8.00 n/a n/a n/a
2014-02-14 2013-12-31 13F TETRA TECH INC CMN STK Cmn Put 900 -70.00 25 -67.95 n/a n/a n/a
2013-11-14 2013-09-30 13F TETRA TECH INC CMN STK Cmn Put 3,000 -57.75 78 -53.29 n/a n/a n/a
2013-08-14 2013-06-30 13F TETRA TECH INC CMN STK Cmn Put 7,100 167 n/a n/a n/a
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.