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iShares MBS ETF

941 hedge funds and large institutions have $34.4B invested in iShares MBS ETF in 2025 Q2 according to their latest regulatory filings, with 98 funds opening new positions, 413 increasing their positions, 313 reducing their positions, and 84 closing their positions.

New
Increased
Maintained
Reduced
Closed

461% more call options, than puts

Call options by funds: $9.16M | Put options by funds: $1.63M

32% more repeat investments, than reductions

Existing positions increased: 413 | Existing positions reduced: 313

17% more first-time investments, than exits

New positions opened: 98 | Existing positions closed: 84

8% more capital invested

Capital invested by funds: $32B → $34.4B (+$2.46B)

0.74% more ownership

Funds ownership: 86.69%87.43% (+0.74%)

1% more funds holding

Funds holding: 936941 (+5)

13% less funds holding in top 10

Funds holding in top 10: 6859 (-9)

Holders
941
Holders Change
+5
Holders Change %
+0.53%
% of All Funds
12.36%
Holding in Top 10
59
Holding in Top 10 Change
-9
Holding in Top 10 Change %
-13.24%
% of All Funds
0.77%
New
98
Increased
413
Reduced
313
Closed
84
Calls
$9.16M
Puts
$1.63M
Net Calls
+$7.53M
Net Calls Change
-$45.8M

MBB Hedge Fund Activity: Q2 2025 in Review

941 of the 7,613 institutional investors tracked by Wall St. Rank reported a position in iShares MBS ETF (MBB) for Q2 2025, worth a combined $34.4B — up 7.7% from $32B a quarter earlier.

Buyers outnumbered sellers: 98 funds opened new MBB positions and 84 closed out — a net gain of 14 holders — while 413 added to existing stakes and 313 trimmed.

The largest buyer was TIAA Trust, National Association, adding an estimated $1.73B. The largest seller was State of Tennessee, Department of Treasury, cutting an estimated $233M.

  • 941 institutional investors held iShares MBS ETF (MBB) as of Q2 2025, up from 936 in Q1 2025.
  • Funds reported $34.4B of iShares MBS ETF stock for Q2 2025, up 7.7% quarter-over-quarter.
  • 98 funds opened new iShares MBS ETF positions in Q2 2025 and 84 closed out, a net change of +14 holders.
  • The largest iShares MBS ETF buyer in Q2 2025 was TIAA Trust, National Association, an estimated $1.73B added.
  • The largest iShares MBS ETF seller in Q2 2025 was State of Tennessee, Department of Treasury, an estimated $233M sold.

Based on aggregated 13F filings for Q2 2025.