Nintendo will profit from videos uploaded by fans that feature its games, the company has confirmed.
Clips posted to YouTube will now display advertising, with income going directly to the Japanese gaming giant.
Some fans have reacted angrily, saying they would no longer play the Nintendo titles, nor upload more clips.
In a statement, the firm said the move was part of an "on-going push to ensure Nintendo content is shared across social media".
"We continually want our fans to enjoy sharing Nintendo content on YouTube," the company added.
"That is why, unlike other entertainment companies, we have chosen not to block people using our intellectual property."
Many games fans enjoy uploading footage of themselves playing popular titles.
Often, these clips - referred to as "Let's Play" (LP) - show how to complete difficult sections, or show off the advanced skills of the gamer.
One popular LP-er, Zack Scott, discovered that Nintendo was issuing what is known as a "content ID match" claim on footage he uploaded of Luigi's Mansion: Dark Moon.
A content ID match allows rights holders to place advertising within videos in order to profit from views.
Importantly, a content ID match means the uploader of the clip - in this case Zack Scott - cannot themselves make money from the advertising.
"I think filing claims against LP-ers is backwards," Mr Scott said in a message posted to Facebook.
"Video games aren't like movies or TV. Each play-through is a unique audiovisual experience."
He argued that viewing footage of games can tempt people to buy it.
"Until their claims are straightened out, I won't be playing their games," he continued.
"I won't because it jeopardises my channel's copyright standing and the livelihood of all LP-ers."
Nintendo defended the move, adding that only clips showing games footage of a certain length would be affected.
"Adverts will now appear at the beginning, next to or at the end of the clips," the company said.