Wikipedia:Global Privacy Control

Global Privacy Control (GPC) is a proposed HTTP header field that can be used to inform websites of the user's wish to have their information not be sold or used by ad trackers. GPC was developed in 2020 by privacy tech researchers such as Wesleyan University professor Sebastian Zimmeck and former Chief Technologist of the Federal Trade Commission Ashkan Soltani, as well as a group of privacy focused companies including the Electronic Frontier Foundation and owner of Tumblr and WordPress, Automattic. The signal has been implemented by privacy extension DuckDuckGo, The New York Times, and privacy browser Brave and is supported by Firefox creator, Mozilla as well as former California Attorney General Xavier Becerra. GPC is a spiritual successor to the Do Not Track header that was created in 2009 but didn't find widespread success due to the lack of legislation that would require companies to legally respect the Do Not Track header. GPC is an attempt to be a valid Do Not Sell My Personal Information signal according to the California Consumer Privacy Act (CCPA), which stipulates that websites are legally required to respect a signal sent by users who want to opt-out of having their personal data sold.