Small addition: This article says Newell bought Harrington out when he left in 2000. https://www.forbes.com/forbes/2011/0228/technology-gabe-newell-videogames-

Small addition: This article says Newell bought Harrington out when he left in 2000. https://www.forbes.com/forbes/2011/0228/technology-gabe-newell-videogames-valve-online-mayhem.html https://www.forbes.com/forbes/2011/0228/technology-gabe-newe...