YouTube has contacted presenters of video game Let's Plays and Walkthroughs to explain its new crackdown on alleged copyright infringements.

In the last week, many owners of successful YouTube channels, which profile and report on video games, have been hit with multiple notices from YouTube, claiming various copyright transgressions. The notices, generated by YouTube's automatic Content ID system, have been controversial, because they sometimes make claims on behalf of games companies that have given permission for content to be used, and sometimes from companies with dubious or tenuous connections to the copyrights.

"Last week, we expanded the system to scan more channels," stated the YouTube email, obtained by Polygon. "As a result, some channels, including many gaming channels, saw claims appear against their videos from audio or video copyright holders."

The email pointed out that some videos can contravene multiple copyrights, including the game publisher and, say, a music rights holder. It went on to advise video makers what steps they can take if they receive a copyright flag. It stressed the issue of music copyrights, which seem to have generated a large number of claims, which lead to advertising revenues from a video diverting from its producer to the claimant.

Some "YouTubers" have been critical of YouTube's handling of its new initiative. The company has previously been almost mute on the episode, restricting itself to a formal statement late last week.

The new statement did not address issues like erroneous claims, or concerns that the copyright sweep seems to be focused on "Affiliate" channels, not owned by, or signed to long-term contracts with larger networks like Polaris and Machinima.

"If you're creating videos with content from other people, remember that rights ownership can be complicated and different owners have different policies," stated the email. "Whether gaming, music or comedy is your passion, know that we love what you do. We've worked hard to design Content ID and other tools to give everyone, from individual creators to media companies, the opportunity to make great videos and earn money. As YouTube grows, we want to make sure we're providing the right product features to ensure that everyone continues to thrive."