ISHARES MBS ETF (MBB) Institutional Ownership and Insiders Activity

ISHARES MBS ETF (MBB) is widely held by institutional investors, with 2 tracked firms reporting positions valued at approximately $10.45M based on SEC Form 13F filings for the quarter ended June 30, 2026.

Renaissance Technologies LLC is the largest disclosed holder, reporting approximately $8.88M in MBB holdings in its latest filing.

Institutional ownership among tracked investors remains highly concentrated, with Renaissance Technologies LLC representing the majority of disclosed value.