Coinbase has confirmed it is one of Strategy's custodians, and blockchain analytics have traced a significant Bitcoin transfer to Fidelity, suggesting multiple custodians are involved.

Strategy has not disclosed specific custodians, only referring to 'various custody' setups, which raises concerns about transparency and security.

In response to SEC inquiries amid industry turmoil, Strategy invoked SEC Rule 83 to keep its custodian details confidential, citing security reasons.

These nine firms, such as Gemini and NYDIG, are well-established in regulatory compliance, narrowing down the potential custodians for Strategy's Bitcoin.

Michael Saylor opposes revealing proof of reserves or detailed custodian lists due to security concerns, though as a public company, some transparency is expected.

While Strategy's official documents recognize Coinbase as the primary market for Bitcoin, Arkham Intelligence reported a transfer of 70,000 BTC from Strategy to Fidelity in May, indicating active management of its assets.

Strategy, a major Bitcoin holder, is maintaining secrecy around its $72 billion Bitcoin holdings by employing multiple undisclosed custodians, with Coinbase confirmed as one of them.

Saylor's cautious stance on Bitcoin has faced criticism from skeptics, especially considering past market collapses, though some supporters appreciate his risk-averse approach.

Regulatory filings reveal that Strategy's custodians are limited to nine U.S.-based, institutional-grade firms regulated by the New York Department of Financial Services, including Fidelity and BitGo.

The secrecy surrounding Strategy's custodians has drawn comparisons to the FTX scandal, where lack of transparency contributed to investor losses.

Coinbase CEO Brian Armstrong indicated that Coinbase holds Bitcoin for eight of the top ten publicly traded Bitcoin holders, implying a connection to Strategy.