iShares 신탁 - iShares MBS ETF
US ˙ NasdaqGM ˙ US4642885887

SecurityMBB / iShares Trust - iShares MBS ETF
InstitutionMorgan Stanley
Latest Disclosed Ownership10,792,188 shares
Latest Disclosed Value $ 1,024,718,333
Morgan Stanley reports 9.54% increase in ownership of MBB / iShares Trust - iShares MBS ETF

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 10,792,188 shares of iShares Trust - iShares MBS ETF (US:MBB) valued at $1,024,718,251 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 9,852,362 shares of iShares Trust - iShares MBS ETF. This represents a change in shares of 9.54% during the quarter. The current value of the position is $1,016,732,031 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 10,792,188 939,826 9.54 1,024,718 9.23 0.0617
2026-05-27 2025-12-31 13F/A-1 ISHARES TR MBS ETF 464288588 9,852,362 383,629 4.05 938,142 4.13 0.0560
2026-02-13 2025-12-31 13F ISHARES TR MBS ETF 464288588 9,852,362 383,629 938,142 0.0560
2026-05-27 2025-09-30 13F/A-1 ISHARES TR MBS ETF 464288588 9,468,733 278,507 3.03 900,950 4.41 0.0545
2025-11-14 2025-09-30 13F ISHARES TR MBS ETF 464288588 9,468,733 278,507 900,950 0.0545
2025-08-15 2025-06-30 13F ISHARES TR MBS ETF 464288588 9,190,226 789,697 9.40 862,870 9.53 0.0562
2025-05-15 2025-03-31 13F ISHARES TR MBS ETF 464288588 8,400,529 -134,505 -1.58 787,802 0.68 0.0563
2025-05-15 2024-12-31 13F/A-1 ISHARES TR MBS ETF 464288588 8,535,034 589,586 7.42 782,492 2.79 0.0548
2025-02-14 2024-12-31 13F ISHARES TR MBS ETF 464288588 8,535,034 589,586 782,492 0.0548
2025-05-14 2024-09-30 13F/A-2 ISHARES TR MBS ETF 464288588 7,945,448 260,437 3.39 761,254 7.89 0.0552
2025-02-14 2024-09-30 13F/A-1 ISHARES TR MBS ETF 464288588 7,945,448 260,437 761,254 0.0552
2024-11-14 2024-09-30 13F ISHARES TR MBS ETF 464288588 7,945,448 260,437 761,254 0.0066
2025-05-14 2024-06-30 13F/A-2 ISHARES TR MBS ETF 464288588 7,685,011 27,055 0.35 705,561 -0.31 0.0546
2024-10-17 2024-06-30 13F/A-1 ISHARES TR MBS ETF 464288588 7,685,011 27,055 705,561 0.0546
2024-08-14 2024-06-30 13F ISHARES TR MBS ETF 464288588 7,685,011 27,055 705,561 0.0546
2024-10-17 2024-03-31 13F/A-2 ISHARES TR MBS ETF 464288588 7,657,956 594,784 8.42 707,748 6.51 0.0568
2024-08-16 2024-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 7,657,956 594,784 707,748 0.0067
2024-05-15 2024-03-31 13F ISHARES TR MBS ETF 464288588 7,657,956 594,784 707,748 0.0568
2024-08-16 2023-12-31 13F/A-1 ISHARES TR MBS ETF 464288588 7,063,172 -773,359 -9.87 664,503 -4.51 0.0586
2024-02-13 2023-12-31 13F ISHARES TR MBS ETF 464288588 7,063,172 -773,359 664,503 0.0586
2023-11-15 2023-09-30 13F ISHARES TR MBS ETF 464288588 7,836,531 -513,940 -6.15 695,884 -10.65 0.0708
2023-08-14 2023-06-30 13F ISHARES TR MBS ETF 464288588 8,350,471 649,808 8.44 778,807 6.76 0.0768
2023-05-15 2023-03-31 13F ISHARES TR MBS ETF 464288588 7,700,663 529,695 7.39 729,484 9.68 0.0782
2023-02-14 2022-12-31 13F ISHARES TR MBS ETF 464288588 7,170,968 1,642,304 29.71 665,107 31.36 0.0755
2022-11-14 2022-09-30 13F ISHARES TR MBS ETF 464288588 5,528,664 57,439 1.05 506,316 -5.08 0.0690
2022-10-27 2022-06-30 13F/A-1 ISHARES TR MBS ETF 464288588 5,471,225 239,097 4.57 533,389 0.07 0.0692
2022-08-15 2022-06-30 13F ISHARES TR MBS ETF 464288588 5,471,225 239,097 533,389 0.0140
2022-10-27 2022-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 5,232,128 -564,302 -9.74 532,997 -14.41 0.0719
2022-05-13 2022-03-31 13F ISHARES TR MBS ETF 464288588 5,232,128 -564,302 532,997 0.0719
2022-02-14 2021-12-31 13F ISHARES TR MBS ETF 464288588 5,796,430 34,567 0.60 622,710 -0.06 0.0769
2021-11-15 2021-09-30 13F ISHARES TR MBS ETF 464288588 5,761,863 210,475 3.79 623,088 3.71 0.0839
2021-08-23 2021-06-30 13F/A-1 ISHARES TR MBS ETF 464288588 5,551,388 328,490 6.29 600,826 6.10 0.0793
2021-08-16 2021-06-30 13F ISHARES TR MBS ETF 464288588 5,551,388 328,490 600,826 0.0165
2021-05-17 2021-03-31 13F ISHARES TR MBS ETF 464288588 5,222,898 230,547 4.62 566,267 2.99 0.0832
2021-02-16 2020-12-31 13F ISHARES TR MBS ETF 464288588 4,992,351 623,365 14.27 549,808 13.99 0.0849
2020-11-13 2020-09-30 13F ISHARES TR MBS ETF 464288588 4,368,986 267,211 6.51 482,335 6.23 0.0933
2020-08-14 2020-06-30 13F ISHARES TR MBS ETF 464288588 4,101,775 272,775 7.12 454,066 7.38 0.1005
2020-05-26 2020-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 3,829,000 514,162 15.51 422,876 18.06 0.1149
2020-05-15 2020-03-31 13F ISHARES TR MBS ETF 464288588 3,829,000 514,162 422,876 32,485.6923
2020-02-14 2019-12-31 13F ISHARES TR MBS ETF 464288588 3,314,838 308,250 10.25 358,202 10.01 0.0833
2019-11-14 2019-09-30 13F ISHARES TR MBS ETF 464288588 3,006,588 564,952 23.14 325,613 23.94 0.0862
2019-08-14 2019-06-30 13F ISHARES TR MBS ETF 464288588 2,441,636 222,443 10.02 262,720 11.31 0.0699
2019-05-15 2019-03-31 13F ISHARES TR MBS ETF 464288588 2,219,193 172,109 8.41 236,032 10.18 0.0668
2019-02-14 2018-12-31 13F ISHARES TR MBS ETF 464288588 2,047,084 -191,821 -8.57 214,228 -7.40 0.0641
2019-04-23 2018-09-30 13F/A-2 ISHARES TR MBS ETF 464288588 2,238,905 166,178 8.02 231,347 7.14 0.0579
2018-11-20 2018-09-30 13F/A-1 ISHARES TR MBS ETF 464288588 2,238,905 0 231,347 0.0579
2018-11-14 2018-09-30 13F ISHARES TR MBS ETF 464288588 2,238,905 166,178 231,347
2019-04-23 2018-06-30 13F/A-1 ISHARES TR MBS ETF 464288588 2,072,727 -180,143 -8.00 215,938 -8.40 0.0583
2018-08-14 2018-06-30 13F ISHARES TR MBS ETF 464288588 2,072,727 -180,143 215,938
2019-04-23 2018-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 2,252,870 101,154 4.70 235,741 2.79 0.0654
2018-05-14 2018-03-31 13F ISHARES TR MBS ETF 464288588 2,252,870 101,154 235,741
2019-04-23 2017-12-31 13F/A-1 ISHARES TR MBS ETF 464288588 2,151,716 211,481 10.90 229,351 10.37 0.0628
2018-02-14 2017-12-31 13F ISHARES TR MBS ETF 464288588 2,151,716 211,481 229,351
2017-11-14 2017-09-30 13F ISHARES TR MBS ETF 464288588 1,940,235 384,522 24.72 207,799 25.11 0.0622
2017-08-11 2017-06-30 13F ISHARES TR MBS ETF 464288588 1,555,713 -34,203 -2.15 166,087 -1.96 0.0502
2017-05-22 2017-03-31 13F/A-1 ISHARES TR MBS ETF 464288588 1,589,916 88,381 5.89 169,406 6.09 0.0521
2017-05-12 2017-03-31 13F ISHARES TR MBS ETF 464288588 1,589,916 169,406
2017-02-22 2016-12-31 13F/A-1 ISHARES TR MBS ETF 464288588 1,501,535 -86,140 -5.43 159,674 -8.65 0.0523
2017-02-13 2016-12-31 13F ISHARES TR MBS ETF 464288588 1,501,535 159,674
2016-11-10 2016-09-30 13F ISHARES TR MBS ETF 464288588 1,587,675 374,676 30.89 174,787 31.03 0.0597
2016-08-12 2016-06-30 13F ISHARES TR MBS ETF 464288588 1,212,999 73,477 6.45 133,393 6.92 0.0482
2016-05-12 2016-03-31 13F ISHARES TR MBS ETF 464288588 1,139,522 187,038 19.64 124,754 21.61 0.0480
2016-02-09 2015-12-31 13F ISHARES TR MBS ETF 464288588 952,484 259,863 37.52 102,582 35.11 0.0371
2016-02-08 2015-09-30 13F/A-1 ISHARES TR MBS ETF 464288588 692,621 61,073 9.67 75,925 10.68 0.0281
2015-11-09 2015-09-30 13F ISHARES TR MBS ETF 464288588 692,621 75,925
2015-08-12 2015-06-30 13F ISHARES MBS ETF 464288588 631,548 -31,080 -4.69 68,599 -6.18 0.0238
2015-05-14 2015-03-31 13F ISHARES MBS ETF 464288588 662,628 88,675 15.45 73,115 16.53 0.0269
2015-02-13 2014-12-31 13F ISHARES MBS ETF 464288588 573,953 136,538 31.21 62,743 32.68 0.0229
2014-12-16 2014-09-30 13F/A-1 ISHARES MBS ETF 464288588 437,415 -94,638 -17.79 47,289 -16.25 0.0182
2014-11-14 2014-09-30 13F ISHARES MBS ETF 464288588 437,415 47,289
2014-05-13 2014-03-31 13F ISHARES MBS ETF 464288588 532,053 -30,551 -5.43 56,467 -4.02 0.0236
2014-02-13 2013-12-31 13F ISHARES MBS ETF 464288588 562,604 -66,683 -10.60 58,832 -11.73 0.0250
2013-11-13 2013-09-30 13F ISHARES BARCLAYS MBSBOND FU COM 464288588 629,287 -180,594 -22.30 66,653 -21.79 0.0315
2013-08-08 2013-06-30 13F ISHARES BARCLAYS MBSBOND FU COM 464288588 809,881 809,881 85,223 0.0430
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.