US professional tennis player and multiple Grand Slam title holder Serena Williams has revealed on her Instagram (Apr 17) that since it was set up in 2014, her investment arm Serena Ventures has been quietly investing in over 30 companies, including major US cryptocurrency exchange Coinbase.

Serena Ventures claims a portfolio with a total market cap worth over $12 billion. It focuses on supporting early-stage companies, investing in those that “embrace diverse leadership, individual empowerment, creativity, and opportunity”. As the company grows, it hopes to also mentor “young founders” and “take burgeoning entrepreneurs to the next level,” says its website.

Details of how much and when the four-time Olympic gold medallist tennis superstar invested in Coinbase through Serena Ventures have not been made public so far.