iShares Trust - iShares MBS ETF
US ˙ NasdaqGM ˙ US4642885887

SecurityMBB / iShares Trust - iShares MBS ETF
InstitutionFmr Llc
Latest Disclosed Ownership356,352 shares
Latest Disclosed Value $ 33,835,615
Fmr Llc reports 1.34% increase in ownership of MBB / iShares Trust - iShares MBS ETF

On May 15, 2026 - Fmr Llc filed a 13F-HR form disclosing ownership of 356,352 shares of iShares Trust - iShares MBS ETF (US:MBB) valued at $33,835,622 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 351,630 shares of iShares Trust - iShares MBS ETF. This represents a change in shares of 1.34% during the quarter. The current value of the position is $33,536,287 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 ISHARES TR MBS ETF 464288588 356,352 4,722 1.34 33,836 1.05 0.0004
2026-02-17 2025-12-31 13F ISHARES TR MBS ETF 464288588 351,630 -2,491 -0.70 33,482 -0.63 0.0017
2025-11-13 2025-09-30 13F ISHARES TR MBS ETF 464288588 354,121 -12,856 -3.50 33,695 -2.21 0.0018
2025-08-14 2025-06-30 13F ISHARES TR MBS ETF 464288588 366,977 -31,343 -7.87 34,456 -7.76 0.0019
2025-05-12 2025-03-31 13F ISHARES TR MBS ETF 464288588 398,320 -23,379 -5.54 37,354 -3.38 0.0024
2025-02-13 2024-12-31 13F ISHARES TR MBS ETF 464288588 421,699 -545,843 -56.42 38,661 -58.29 0.0023
2024-11-13 2024-09-30 13F ISHARES TR MBS ETF 464288588 967,542 -850,404 -46.78 92,700 -44.46 0.0056
2024-08-13 2024-06-30 13F ISHARES TR MBS ETF 464288588 1,817,946 16,697 0.93 166,906 0.26 0.0107
2024-05-13 2024-03-31 13F ISHARES TR MBS ETF 464288588 1,801,249 -94,192 -4.97 166,471 -6.65 0.0112
2024-02-13 2023-12-31 13F ISHARES TR MBS ETF 464288588 1,895,441 15,200 0.81 178,323 6.80 0.0137
2023-11-13 2023-09-30 13F ISHARES TR MBS ETF 464288588 1,880,241 -86 -0.00 166,965 -4.79 0.0144
2023-08-11 2023-06-30 13F ISHARES TR MBS ETF 464288588 1,880,327 1,001,958 114.07 175,369 110.76 0.0147
2023-08-11 2023-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 878,369 659,074 300.54 83,208 309.10 0.0076
2023-05-11 2023-03-31 13F ISHARES TR MBS ETF 464288588 878,369 659,074 83,208 0.0076
2023-02-13 2022-12-31 13F ISHARES TR MBS ETF 464288588 219,295 10,291 4.92 20,340 6.26 0.0020
2022-11-10 2022-09-30 13F ISHARES TR MBS ETF 464288588 209,004 71,614 52.12 19,141 42.91 0.0020
2022-08-12 2022-06-30 13F ISHARES TR MBS ETF 464288588 137,390 -48,538 -26.11 13,394 -29.29 0.0013
2022-05-13 2022-03-31 13F ISHARES TR MBS ETF 464288588 185,928 99,332 114.71 18,941 103.58 0.0015
2022-02-14 2021-12-31 13F ISHARES TR MBS ETF 464288588 86,596 21,863 33.77 9,304 32.90 0.0007
2022-02-14 2021-09-30 13F/A-1 ISHARES TR MBS ETF 464288588 64,733 2,163 3.46 7,001 3.38 0.0006
2021-11-15 2021-09-30 13F ISHARES TR MBS ETF 464288588 64,733 2,163 7,001 0.0001
2021-08-13 2021-06-30 13F ISHARES TR MBS ETF 464288588 62,570 -14,446 -18.76 6,772 -18.90 0.0005
2021-05-14 2021-03-31 13F ISHARES TR MBS ETF 464288588 77,016 -1,921,325 -96.15 8,350 -96.21 0.0007
2021-02-08 2020-12-31 13F ISHARES TR MBS ETF 464288588 1,998,341 -813,217 -28.92 220,078 -29.10 0.0196
2020-11-13 2020-09-30 13F ISHARES TR MBS ETF 464288588 2,811,558 -91,558 -3.15 310,396 -3.42 0.0314
2020-08-24 2020-06-30 13F/A-1 ISHARES TR MBS ETF 464288588 2,903,116 -85,453 -2.86 321,375 -2.63 0.0353
2020-08-13 2020-06-30 13F ISHARES TR MBS ETF 464288588 2,903,116 -85,453 321,375 7,895.2433
2020-05-14 2020-03-31 13F ISHARES TR MBS ETF 464288588 2,988,569 -74,430 -2.43 330,058 -0.28 0.0457
2020-02-07 2019-12-31 13F ISHARES TR MBS ETF 464288588 3,062,999 1,640,631 115.35 330,987 114.87 0.0365
2019-11-13 2019-09-30 13F ISHARES TR MBS ETF 464288588 1,422,368 15,020 1.07 154,043 1.73 0.0185
2019-08-13 2019-06-30 13F ISHARES TR MBS ETF 464288588 1,407,348 -11,353 -0.80 151,430 0.36 0.0177
2019-05-13 2019-03-31 13F ISHARES TR MBS ETF 464288588 1,418,701 1,417,393 108,363.38 150,893 110,850.74 0.0181
2019-02-13 2018-12-31 13F ISHARES TR MBS ETF 464288588 1,308 707 117.64 136 119.35 0.0000
2018-11-09 2018-09-30 13F ISHARES TR MBS ETF 464288588 601 601 62 0.0000
2017-02-10 2016-12-31 13F ISHARES TR MBS ETF 464288588 0 -2,077 -100.00 0 -100.00
2016-11-14 2016-09-30 13F ISHARES TR MBS ETF 464288588 2,077 2,077 229 0.0000
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.