Reddit co-founder Alexis Ohanian - who may be better known as the husband of tennis star Serena Williams - called on Friday for his seat on the board of the social news company to be given to a black candidate.
Ohanian said in an online post that he resigned from the board of Reddit, which he co-founded 15 years ago.
He vowed to use any future gains on his stock in the enterprise to serve the black community, predominantly by curbing racial hate.
Ohanian also pledged a million dollars to former NFL star Colin Kaepernick's Know Your Rights Camp.
"It's long overdue to do the right thing," Ohanian said in a video posted online.
"I'm saying this as a father who needs to be able to answer his black daughter when she asks 'What did you do?'"
Ohanian and Williams married three years ago and have one child.
"I believe resignation can actually be an act of leadership from people in power right now," the 37-year-old Reddit co-founder said.
"To everyone fighting to fix our broken nation: do not stop."
Reddit chief executive Steve Huffman said in a blog post this week that the online bulletin board is exploring what it can do to give people a voice and be an impetus for change when it comes to racial justice.
"We work for this platform because we care deeply about community and belonging," Huffman said.
"But community and belonging are not possible without safety from violence, and now is the time to stand in solidarity with the Black members of our communities."
Reddit last year "quarantined" a popular forum of supporters of President Donald Trump, claiming users repeatedly violated platform rules by promoting violence.