Circle USYC (originally Hashnote Short Duration Yield Fund's USYC token) is a tokenised fund that invests in short-term US Treasury bills and performs repo/reverse repo activities. Circle acquired Hashnote in January 2025 and integrated USYC into its product stack. The token represents shares in a fund that earns short-term risk-free rate returns. It is designed for institutional and accredited investors — not retail users. USYC is notably used as the backing asset for Ethena's USDtb stablecoin, giving it a key role in the growing DeFi stablecoin ecosystem.
USYC is designed as on-chain T-Bill exposure — holders earn approximately 4-5% APY from short-term US government securities, accrued directly into the token's price (the token appreciates slightly rather than distributing yield). This makes it useful as a yield-bearing collateral asset in DeFi protocols, particularly for stablecoin backing, lending markets, and treasury management. It operates on Ethereum and is one of the most liquid tokenised Treasury products available. Trading volume is very thin ($112,000 daily) because it is primarily a hold-to-earn instrument rather than an active trading token.
USYC has approximately 2.6 billion tokens in circulation, with a market cap of approximately $2.9 billion. The token price gradually appreciates from $1.00 as T-Bill yield accrues — it currently trades at approximately $1.12, reflecting accumulated yield since launch. This is fundamentally different from a pegged stablecoin. The token has no upside beyond Treasury yield rates.
USYC competes with BlackRock's BUIDL, Franklin Templeton's BENJI, and other tokenised Treasury fund products. It has achieved significant scale by being adopted as the primary backing asset for Ethena's USDtb, which links it to Ethena's $2 billion+ user base. This captive institutional demand is a meaningful competitive advantage.
USYC is explicitly restricted to institutional and accredited investors — retail investors in Ireland and most jurisdictions cannot access it directly. Its yield is tied to short-term US interest rates; if rates fall significantly, yield collapses. As a relatively new tokenised fund product, there is limited track record compared to traditional T-Bill funds. Regulatory changes to tokenised fund structures could impact its structure.
Tokenised Treasury products become standard DeFi collateral infrastructure, further stablecoin protocols adopt USYC as backing, or interest rates remain elevated providing strong ongoing yield.
US interest rates fall significantly reducing USYC's yield appeal, regulatory frameworks restrict tokenised fund products, or competing products like BUIDL capture the institutional DeFi market.
We would become more positive if: USYC becomes accessible to retail investors through a regulated fund wrapper, additional major DeFi protocols adopt USYC as collateral, or institutional AUM grows significantly. We would become more cautious if: US interest rates fall sharply reducing yield, or Ethena moves away from USYC as USDtb's primary backing asset.
Circle USYC is important institutional infrastructure — the T-Bill yield layer that backs Ethena's USDtb and increasingly underpins institutional DeFi. It is not a retail investment product and cannot be directly accessed by most Irish investors. Understanding it is valuable context for understanding how advanced stablecoins are constructed, but it is not a product for direct retail investment.
Access note: USYC is restricted to institutional and accredited investors. Irish retail investors cannot directly hold USYC. Its importance is as infrastructure backing other DeFi products like Ethena's USDtb, not as a direct investment vehicle.