Valve has made a number of changes to the Steam Subscriber Agreement today, chief among them a new clause that requires users to clearly disclose when they are using a Steam service to promote a product, service or event in exchange for money, free games or other rewards.

Back in October Valve updated its Steam Curator guidelines to stipulate that they disclose paid-for recommendations, but this seems to be the first time such a requirement has been added to the Steam User Agreement itself.

The new clause encompasses all Steam services, including its nascent Steam Broadcasting video streaming system, and seems to fall in line with the FTC's disclosure requirements for paid YouTuber content.

Gamasutra initially became aware of the new guidelines thanks to an update from the Steam Database Twitter account, and verified the changes by comparing text of the current agreement (linked above) to a cached version from yesterday retrieved via the Wayback Machine.