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FundLens / Funds / MBB

iShares MBS ETF (MBB)

SEC CIK 1100663 · Series S000013702 · Portfolio as of 2026-05-31

Net assets
$38.74B
Holdings
11146
Snapshots
27
History since
2019-11-30

Top holdings

SecurityValueWeight
BLACKROCK CASH FUNDS · XTSLA$2.62B6.46%
Freddie Mac · FR SD8146$405.6M1.00%
Government National Mortgage Association · G2SF 5.5 6/11$367.1M0.90%
UMBS, TBA · FNCL 5.5 6/11$322.2M0.79%
Government National Mortgage Association · G2SF 5 6/11$260.2M0.64%
UMBS, TBA · FNCL 5 6/11$249.2M0.61%
Government National Mortgage Association · G2 MB0025$213.0M0.52%
Government National Mortgage Association · G2 MA7648$209.9M0.52%
Government National Mortgage Association · G2 MA7766$206.3M0.51%
Fannie Mae · FN MA4492$202.3M0.50%

Sector exposure

other
98.9%
fixed income
0.9%

Recent monthly returns

2025-12
+0.13%
2026-01
+0.48%
2026-02
+1.62%
2026-03
-1.62%
2026-04
+0.08%
2026-05
+0.28%

From N-PORT Part B, units verified by net-asset reconciliation.

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Full holdings, every historical snapshot, point-in-time queries, monthly returns and flows — free tier available, no card required.

Source: SEC EDGAR Form N-PORT. Data is quarterly with a regulatory filing lag; this page shows the most recent public filing. Not investment advice.