People are taking advantage of Steam's trading card system by creating fake games, collecting cards from those games with bot accounts, and selling them to collectors for profit. Valve is not having it anymore.

Valve announced Tuesday that new games put on the Steam store won't dole out trading cards to players until Valve is confident that the game is being bought and played by legitimate users. Once a game reaches a "confidence metric" based on an unspecified "variety of data," developers will be able to hand out trading cards to players.

The trading card system -- introduced back in 2013 -- allows developers to create trading cards to reward players with just for spending time in the game (or if the games are free to play, rewarding players for spending money within the game). Some players collect these cards or buy them on the Steam community marketplace to round out their sets. Some players sell their cards to profit off of the marketplace, and some players ignore the whole thing completely.

By collecting a full set, players can customize their Steam profiles, earn discounts for other games, or get experience to level up their Steam account.

"Bad actors" are taking advantage of this system by creating fake games that include trading cards and publishing them on Steam. As the developer, they can generate thousands of game keys for bot accounts, which sit in the game and accrue trading cards en masse. Then they sell the cards to collectors.

It sounds like a no-harm-no-foul situation: those people are profiting from collectors who are willing to spend their money on the cards whether they like the game or not. If people want the cards from the fake games, why does Valve care?

Valve doesn't want fake games on Steam. Because bot accounts are putting real hours into these fake games, the fake games have a chance of popping up as a suggestion for players to purchase. Valve doesn't want people to have to figure out whether a game is real or not or end up spending money on a fake game -- it makes Steam look bad.

As for how much this is going to impact legitimate games that want to give their players trading cards, Valve said its hopeful the change will have "little negative impact on other developers and players, with a small number of games having a delay before their trading cards start to drop."