FlexShares Trust - FlexShares iBoxx 3-Year Target Duration TIPS Index Fund
US ˙ ARCA ˙ US33939L5066

SecurityTDTT / FlexShares Trust - FlexShares iBoxx 3-Year Target Duration TIPS Index Fund
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership104,930 shares
Latest Disclosed Value $ 2,543,503
Citadel Advisors Llc reports 11.43% increase in ownership of TDTT / FlexShares Trust - FlexShares iBoxx 3-Year Target Duration TIPS Index Fund

On May 15, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 104,930 shares of FlexShares Trust - FlexShares iBoxx 3-Year Target Duration TIPS Index Fund (US:TDTT) valued at $2,543,503 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 94,164 shares of FlexShares Trust - FlexShares iBoxx 3-Year Target Duration TIPS Index Fund. This represents a change in shares of 11.43% during the quarter. The current value of the position is $2,513,074 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)
2026-05-15 2026-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 104,930 10,766 11.43 2,544 12.27 0.0004
2026-02-17 2025-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 94,164 -2,748 -2.84 2,266 -3.90 0.0003
2025-11-14 2025-09-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 96,912 -29,794 -23.51 2,358 -23.25 0.0004
2025-08-14 2025-06-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 126,706 -37,456 -22.82 3,071 -23.26 0.0005
2025-05-15 2025-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 164,162 26,308 19.08 4,002 23.10 0.0008
2025-02-14 2024-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 137,854 137,854 3,252 0.0006
2024-11-14 2024-09-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 0 -32,003 -100.00 0 -100.00
2024-08-14 2024-06-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 32,003 11,591 56.79 755 55.79 0.0002
2024-05-15 2024-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 20,412 -42,801 -67.71 485 -67.58 0.0001
2024-02-14 2023-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 63,213 45,927 265.69 1,493 273.25 0.0003
2023-11-14 2023-09-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 17,286 -34,628 -66.70 401 -67.24 0.0001
2023-08-14 2023-06-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 51,914 -9,709 -15.76 1,222 -18.00 0.0003
2023-05-15 2023-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 61,623 -388,392 -86.31 1,489 -85.93 0.0003
2023-02-14 2022-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 450,015 450,015 10,584 0.0025
2022-11-14 2022-09-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 0 -11,088 -100.00 0 -100.00
2022-08-15 2022-06-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 11,088 -3,561 -24.31 275 -27.63 0.0001
2022-05-16 2022-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 14,649 1,328 9.97 380 8.57 0.0001
2022-02-14 2021-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 13,321 -224,920 -94.41 350 -94.42 0.0001
2021-11-15 2021-09-30 13F FLEXSHARES TR Cmn 33939L506 238,241 238,241 6,267 0.0013
2021-08-16 2021-06-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 0 -148,299 -100.00 0 -100.00
2021-05-21 2021-03-31 13F/A-1 FLEXSHARES TR IBOXX 3R TARGT 33939L506 148,299 9,447 6.80 3,911 7.95 0.0010
2021-05-17 2021-03-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 148,299 9,447 3,911 0.0010
2021-02-16 2020-12-31 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 138,852 95,298 218.80 3,623 221.76 0.0009
2020-11-16 2020-09-30 13F FLEXSHARES TR IBOXX 3R TARGT 33939L506 43,554 -33,741 -43.65 1,126 -42.37 0.0003
2020-08-14 2020-06-30 13F FLEXSHARES TR Cmn 33939L506 77,295 -7,219 -8.54 1,954 -5.97 0.0007
2020-05-15 2020-03-31 13F FLEXSHARES TR Cmn 33939L506 84,514 -74,719 -46.92 2,078 -47.19 0.0009
2020-02-14 2019-12-31 13F FLEXSHARES TR Cmn 33939L506 159,233 113,615 249.06 3,935 250.71 0.0017
2019-11-14 2019-09-30 13F FLEXSHARES TR Cmn 33939L506 45,618 -18,663 -29.03 1,122 -29.30 0.0005
2019-08-14 2019-06-30 13F FLEXSHARES TR Cmn 33939L506 64,281 38,065 145.20 1,587 148.75 0.0007
2019-05-15 2019-03-31 13F FLEXSHARES TR Cmn 33939L506 26,216 26,216 638 0.0003
2019-02-14 2018-12-31 13F FLEXSHARES TR Cmn 33939L506 0 -21,831 -100.00 0 -100.00
2018-11-13 2018-09-30 13F FLEXSHARES TR Cmn 33939L506 21,831 9,804 81.52 523 79.11 0.0002
2018-08-14 2018-06-30 13F/A-1 FLEXSHARES TR Cmn 33939L506 12,027 12,027 292 0.0001
2018-08-10 2018-06-30 13F FLEXSHARES TR Cmn 33939L506 12,027 12,027 292
2018-05-14 2018-03-31 13F/A-1 FLEXSHARES TR Cmn 33939L506 0 -10,440 -100.00 0 -100.00
2018-02-09 2017-12-31 13F FLEXSHARES TR Cmn 33939L506 10,440 -29,963 -74.16 254 -74.80 0.0002
2017-05-12 2017-03-31 13F FLEXSHARES TR Cmn 33939L506 40,403 -15,644 -27.91 1,008 -27.17 0.0009
2017-02-10 2016-12-31 13F FLEXSHARES TR Cmn 33939L506 56,047 56,047 1,384 0.0014
2016-08-12 2016-06-30 13F FLEXSHARES IBOXX 3-YEAR TARG Cmn 33939L506 0 -18,698 -100.00 0 -100.00
2017-01-31 2016-03-31 13F/A-1 FLEXSHARES TR Cmn 33939L506 18,698 1,606 9.40 463 12.11 0.0006
2016-05-13 2016-03-31 13F FLEXSHARES IBOXX 3-YEAR TARG Cmn 33939L506 18,698 463
2017-01-31 2015-12-31 13F/A-1 FLEXSHARES TR Cmn 33939L506 17,092 1,368 8.70 413 8.12 0.0005
2016-02-12 2015-12-31 13F FLEXSHARES IBOXX 3-YEAR TARG Cmn 33939L506 17,092 413
2015-06-26 2014-12-31 13F/A-2 FLEXSHARES IBOXX 3-YEAR TARG Cmn 33939L506 15,724 15,724 382 0.0021
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.