LOS ANGELES – Google Inc. is altering its search results to de-emphasize the websites of repeat copyright offenders and make it easier to find legitimate providers of music, movies and other content.

The move is a peace offering to Hollywood and the music recording labels. This year, Google joined other Silicon Valley heavyweights to help kill legislation that would have given government and content creators more power to shut down foreign websites that promote piracy.

The Motion Picture Association of America issued a lukewarm response, saying it was “optimistic” the change would help steer consumers away from piracy.

“We will be watching this development closely — the devil is always in the details,” MPAA senior executive president Michael O’Leary said.

Next week, Google will start using “valid copyright removal notices” to rank its search results, according to a Friday blog post by senior vice president of engineering Amit Singhal.

Google typically ranks websites based on how many other sites link to them, on the belief that sites that get more links are more trustworthy and useful. But Google also regularly tweaks its formulas to reflect special circumstances.

In this case, sites with high numbers of copyright-removal notices may get bumped down in rankings. In effect, that will help users find legitimate sources of content without removing any pages from its results completely.

Last month, Google said it would offer a $50-per-month TV package over a super-fast fiber network in a Kansas City test bed. The package would offer mainstream channels including Viacom Inc.’s Nickelodeon.

Google, which is based in Mountain View, Calif., also sells movies and music through its Google Play store on mobile devices that use its Android operating system.

But a $1 billion copyright lawsuit filed by Viacom against Google’s YouTube in 2007 was re-instated by a federal appeals court in April after a lower court threw it out.

Last week, court papers showed the Authors Guild is demanding Google pay $750 for each of 20 million books it scanned, in a seven-year-old case.