Circle’s Worst Day as a Public Company Wasn’t About Losing Customers

Circle, the issuer of the USDC stablecoin, fell 17% in a single trading session — its worst day since going public roughly thirteen months earlier. Most coverage in the immediate aftermath framed the move simply as fear of new competition, which understates what was actually happening in the stock.

Circle earns almost all of its revenue one way: interest income on the pool of dollars held in reserve behind every USDC token in circulation. In its most recent quarter, that source accounted for roughly 94% of total revenue. A newly announced rival, Open USD, directly attacks that model by proposing to share the same interest income with the businesses that hold its stablecoin, rather than letting the issuer keep all of it — an approach that, if it gains traction, makes Circle’s core business model optional for any business choosing which stablecoin to route its money through.

The part of the story that matters most for Circle specifically isn’t the USDC already embedded in decentralized finance protocols like Aave and Curve — that supply is genuinely sticky, built on years of technical integration that isn’t easily undone. The real exposure is forward-looking: Circle has publicly targeted $150 billion in USDC supply by the second half of 2026, up from roughly $77 billion at the time of the sell-off. That means the company needs close to $73 billion in new stablecoin adoption to show up before year-end, much of it from exactly the kind of business use cases Open USD is now competing for directly.

There’s a second layer sitting on top of this. Circle’s largest distribution partner, Coinbase, already shares a substantial portion of Circle’s reserve income, and that arrangement is up for renewal later this year — with Coinbase also listed among the companies backing the new rival stablecoin. It’s a useful case study in reading past a scary single-day headline number to the specific, quantifiable mechanism actually driving it, rather than treating “competitor emerges” as the whole story.