Valve is distancing itself from gambling services affiliated with its most popular Steam titles.

The company said this week it will "start sending notices" to the sites in question, requesting they cease operations through Steam. Valve will "further pursue the matter as necessary," said Erik Johnson, Valve business development authority.

In 2011, Valve enabled Steam users to exchange in-game items for virtual money and merchandise. But the system eventually spawned a number of spin-off sites that let folks (including underage kids) bet those items for real-world money.

One of them, CS:GO Lotto, made headlines last week when it was revealed to be run by two YouTube stars who were using YouTube to promote CS:GO Lotto, without disclosing that they actually owned it.

Now, Valve is the target of two lawsuits alleging its compliance in illegal gambling "by allowing millions of Americans to link their individual Steam accounts to third-party websites," one suit claimed, suggesting these services don't require age verifications and allow minors to unlawfully place bets.

"A number of gambling sites started leveraging the Steam trading system, and there's been some false assumptions about our involvement with these sites," Valve's Johnson responded in a blog post.

"We'd like to clarify that we have no business relationships with any of these sites," he continued. "We have never received any revenue from them. And Steam does not have a system for turning in-game items into real-world currency."

In fact, people using the five-year-old trading system to gamble skins and hats are, as The Verge reports, in violation of Steam's terms of service.