BlackRock Bitcoin warning In a rare move, BlackRock has quietly added a new line to its iShares Bitcoin Trust (IBIT) filing — and it is turning heads. The update, submitted in early May 2025, flags quantum computing as a potential risk to Bitcoin's long-term security.The filing specifically warns that if quantum tech advances far enough, it could break the cryptographic systems that secure Bitcoin. In their words, it could "undermine the viability" of the cryptographic algorithms used not just in digital assets but across the global tech stack.It's the first time you've seen the world's largest asset manager call out this threat so directly in a Bitcoin-related disclosure, and it says a lot about how seriously institutional players are starting to take future-proofing crypto.Yes, exchange-traded fund (ETF) risk disclosures tend to be exhaustive by nature.