Circle’s USYC Dethrones BlackRock’s BUIDL; Binance Whale Wallet Holds 94% of Supply

Circle’s USYC (US Yield Coin) has flipped BlackRock’s BUIDL to become the world’s largest tokenized money market fund, a shift driven almost entirely by a single massive counterparty.

Data from rwa.xyz confirms the flippening: USYC assets swelled to $1.69 billion (+11% in 30 days), edging out BUIDL’s $1.68 billion (-2.85%). The move cements a symbolic victory for crypto-native infrastructure over Wall Street’s debutante, but the composition of that capital tells a different story.

The Binance Factor

This isn’t organic retail adoption. It’s a B2B infrastructure play. Binance holds approximately $1.43 billion of USYC, representing a staggering 94% of the total supply.

The concentration stems from Binance’s July 2025 integration of USYC as collateral for institutional clients. While BlackRock’s BUIDL serves a diversified base of 103 distinct institutional holders, USYC functions effectively as a specialized liquidity utility for the world’s largest exchange.

The tokenized treasury market has crossed $10.07 billion, with Circle and BlackRock now controlling one-third of the entire sector.

Utility vs. Treasury

The divergence highlights two competing models in the $10 billion RWA sector:

• BlackRock (BUIDL): A diversified, chain-agnostic treasury vehicle used primarily for on-chain cash management and settlement between varying entities.
• Circle (USYC): A specialized collateral instrument. Following Circle’s acquisition of Hashnote last year, the fund has been re-engineered to plug directly into exchange margin engines.

Market makers utilizing USYC on Binance can offset margin requirements while earning yield, a capital efficiency loop that BUIDL, which largely sits idle in wallets, currently lacks.

Institutional Context

This flip validates the “collateral utility” thesis over pure “store of value” for tokenized treasuries. However, the centralization risk is palpable. A shift in Binance’s collateral policy or a regulatory chokepoint on the exchange could vaporize USYC’s lead overnight. BUIDL’s slow bleed (-2.85%) suggests capital rotating out of idle treasury positions into higher-beta opportunities as the wider crypto market heats up, while USYC’s sticky utility keeps its AUM locked in.