So on Sept. 6, Goh says, he took some British pounds from an in-house research-and-development fund at skew. converted those into bitcoin, and then used the proceeds to buy 10 S&P 500 call spreads – a popular type of option – from Crypto Garage, all under a new smart contract, with terms agreed to by both counterparties in minutes. The expiration date for the options was set for the third Friday of the month, similar to the standard practice on many exchanges.

https://www.coindesk.com/tiny-217-options-trade-on-bitcoin-blockchain-could-be-wall-streets-death-knell