Machinima Inc., a popular distributor of online videos about games, agreed to settle charges that it didn’t tell viewers it paid some influential publishers to post videos about Microsoft Corp.’s Xbox One system and games.

The Federal Trade Commission on Wednesday said Machinima, an early leader in so-called multichannel networks, paid “influencers” as part of marketing campaign managed by Microsoft’s advertising agency, Starcom MediaVest Group. Machinima guaranteed Starcom that the “influencer” videos would be viewed at least...