Sam Bankman-Fried, the CEO of crypto exchange FTX, has taken a 7.6% stake in Robinhood, according to a Thursday filing with the Securities and Exchange Commission.Shares of the investing company jumped 36% at one point in extended trading before pulling back. They were last up about 25%.In regular trading Thursday the stock hit an all-time low. Robinhood ended the session priced at $8.56, about 77% away from its IPO price last July.According to the document, Emergent Fidelity Technologies took a stake worth $648 million in Robinhood. Bankman-Fried is the sole director and majority owner, it says.Sam Bankman-Fried, CEO of FTX US Derivatives, testifies during the House Agriculture Committee hearing titled Changing Market Roles: The FTX Proposal and Trends in New Clearinghouse Models, in Longworth Building on Thursday, May 12, 2022.Tom Williams | CQ-Roll Call, Inc. | Getty ImagesThe document goes on to say Bankman-Fried acquired the shares in the belief that they “represent an attractive investment.” “The Reporting Persons intend to hold the Shares as an investment, and do not currently have any intention of taking any action toward changing or influencing the control of the Issuer,” it says. Though the filing also said he may “from time to time engage in discussions” with management.”Of course we think it is an attractive investment too,” Robinhood’s communications team said in a tweet Thursday evening in response to the news of the investment.Bankman-Fried currently has no intention to take other actions but at some point if circumstances change, he may review “options for enhancing stockholder value through, among other things, various strategic alternatives or operational or management initiatives,” according to the document. It also says he could acquire additional shares.FTX, where Bankman-Fried is CEO, is one of the largest crypto exchanges in the world and offers derivatives products for more sophisticated traders as well as spot trading. FTX has become a rival to Coinbase and Binance, though it doesn’t offer its services in the U.S.Robinhood got its start allowing retail investors to invest in stocks but saw huge success when it rolled out its crypto trading platform in 2018. Crypto trading has since become important for the company’s bottom line. In the fall Robinhood revealed its testing a crypto wallet and said the waitlist for it had topped 1 million customers.