ChainCatcher news, according to a filing submitted to the U.S. Securities and Exchange Commission (SEC) this Friday, Fidelity has applied to register the "OnChain" stock class for its tokenized U.S. money market fund, Fidelity Treasury Digital Fund (FYHXX), which was launched at the end of last year and holds cash and U.S. Treasury securities.According to the relevant document, the "OnChain" class of the FYHXX fund currently uses the Ethereum network and may expand to other blockchains in the future. This registration is subject to regulatory approval and is expected to take effect on May 30.