Valve Issues DMCA Notices to Fan Projects, Marking Shift in Policy

Fan-made games Team Fortress: Source 2 and Portal 64 shut down following notices from Valve, surprising the gaming community.

Valve has issued DMCA takedown notices to two fan projects, Team Fortress: Source 2 and Portal 64, marking a shift in the company's typically lenient stance towards fan-made games.
Team Fortress: Source 2 was a fan project aiming to port the 2007 multiplayer shooter, Team Fortress 2, to the newer Source 2 engine.
Portal 64 was a project intended to demake 2007’s Portal to run on the Nintendo 64 hardware.
Both projects have now been shut down following the DMCA notices from Valve.
The move has surprised the gaming community, as Valve has historically supported fan endeavors based on their games.