BlackRock, a major asset management firm, disclosed in SEC filings on May 28 that it added $4.1 million worth of its spot Bitcoin ETF shares to two of its funds.

The company allocated $3.6 million of its iShares Bitcoin Trust (IBIT) shares to the BlackRock Strategic Income Opportunities Portfolio (BSIIX). Additionally, it invested $486,000 of IBIT shares into its BlackRock Strategic Global Bond Fund (MAWIX).

These purchases were part of first-quarter 2024 additions, following BlackRock's earlier plans disclosed in SEC filings on March 8 to integrate IBIT into its various funds. The firm had previously reported holding $6.6 million of IBIT shares in a 13F filing on May 10.

BlackRock's investment strategy aligns it with numerous other investors in IBIT, as evidenced by disclosures indicating at least 422 firms holding IBIT shares as of May 28, according to Fintel data. This positions IBIT as the most widely held spot Bitcoin ETF, with approximately half of the 929 firms reporting investments in the first quarter.

Among these investors, Millennium Management and Schonfeld Strategic Advisors hold the largest positions in IBIT, with $844.2 million and $248.0 million, respectively. Additionally, globally systematically important banks (G-SIBs) such as JP Morgan Chase, Bank of America, BNY Mellon, BNP Paribas, UBS, and Royal Bank of Canada have also invested in IBIT.

IBIT continues to lead in terms of net flows, with $16.4 billion reported as of May 24, surpassing the second highest net flows of Fidelity’s FBTC. As of May 28, IBIT managed $17.2 billion in assets under management (AUM), constituting 31% of the combined AUM of all spot Bitcoin ETFs.

In comparison, Grayscale’s GBTC holds $20 billion in AUM but has seen $17.7 billion in net outflows since its inception.