In 2014, Koum and Acton agreed to sell WhatsApp to Facebook for approximately US$19 billion in cash and stock. Forbes estimates that Acton held over 20% stake in the company, making his net worth around $3.8 billion. According to Acton's personal Twitter feed, he was turned down for employment by both Twitter and Facebook in 2009.
Since 2014, Brian Acton and his wife Tegan Acton started to build a philanthropic network through the foundation Wildcard Giving, with three sister foundations: Sunlight Giving, Acton Family Giving and Solidarity Giving.
The couple started Sunlight Giving in 2014, a family foundation dedicated to supporting the basic services of low-income families with young children ages 0–5. It also provides support for safe spaces and organizations that ensure food security, housing stability, and healthcare access. The foundation supports low-income families with children age five and below living in the San Francisco Bay Area. It's a sister organization belonging to the Wildcard Giving family. Sunlight Giving has $470 million in assets. It granted $6.4 million in 2015, $19.2 million in 2016, and $23.6 million in 2017. This private foundation helped to fund Magnify Community, a non-profit organization with the goal of redirect philanthropists' givings to nonprofits..
Also in 2014, Acton helped establish Acton Family Giving and Solidarity Giving.