Google cofounder Sergey Brin has spent $102 million to fight California’s proposed billionaire tax—he could owe $13 billion if he loses

Google cofounder Sergey Brin has now spent more than nine figures combating California’s proposed wealth tax. According to filings, Brin donated a total of $102 million to the group Building a Better California, a PAC and political advocacy organization opposing the state’s billionaire tax and supporting other pro-business policies and housing and infrastructure affordability. Campaign filings show efforts to block this tax have exceeding $187 million, making Brin the largest sole contributor to the…