Decentralized crypto exchange Orca will restrict U.S. users from trading coins via the front end of its website beginning on March 31, a blow to accessibility for the Solana blockchain’s top DEX.

In a notice published to its website Thursday, Orca said it is “adding the United States to the regions and countries which are restricted from trading on orca.so,” its website The notice didn't provide a reason for the move or why it was coming now. Orca co-founder Grace Kwan didn't immediately respond to a request for comment.

The policy change won't affect traders who directly use Orca’s smart contracts – the infrastructure executing token swaps on-chain. That may provide some reprieve for trading volume because much of Orca’s order flow comes via Jupiter, a trade aggregator that plugs into Orca's back end.

Orca had $280 million in trading volume over the last week, according to DefiLlama. That was nearly three times more than the trading volume on Raydium, Solana’s second-most popular decentralized-finance trading venue.

Orca keeps trades flowing by pooling token liquidity from its users. They loan their assets to the exchange and get a slice of fee revenue in return. The new restrictions don't apply to U.S.-based liquidity providers, according to the notice.

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Danny Nelson

Danny is CoinDesk's managing editor for Data & Tokens. He formerly ran investigations for the Tufts Daily. At CoinDesk, his beats include (but are not limited to): federal policy, regulation, securities law, exchanges, the Solana ecosystem, smart money doing dumb things, dumb money doing smart things and tungsten cubes. He owns BTC, ETH and SOL tokens, as well as the LinksDAO NFT.