NEW YORK, July 30 (Reuters) - Zillow ( ZG ) was sued on

Wednesday by real estate information provider CoStar Group ( CSGP )

, which accused the largest U.S. online real estate

portal of publishing at least 46,979 copyrighted photos without

permission.

The complaint filed in Manhattan federal court seeks

unspecified compensatory and punitive damages, which Arlington,

Virginia-based CoStar ( CSGP ) estimated could exceed $1 billion.

Zillow ( ZG ) did not immediately respond to requests for comment.

CoStar ( CSGP ), which operates real estate listing websites

Apartments.com and Homes.com, accused Seattle-based Zillow ( ZG ) of

exploiting the photos to boost its rental listings business.

According to the complaint, Zillow ( ZG ) uses the photos to induce

property managers and landlords to "claim" properties that are

not actively listed for rent, and then sells advertising

packages and tools to generate revenue.

CoStar ( CSGP ) said Zillow ( ZG ) also distributes some photos under

syndication agreements to rival portals Realtor.com and Redfin,

owned respectively by News Corp ( NWSA ) and Rocket Cos ( RKT ).

Zillow's ( ZG ) "free-riding" on the photos results in infringement

"on a massive scale, however measured," CoStar ( CSGP ) said.

CoStar ( CSGP ) said it provides limited licenses of its photos,

including many that are watermarked, to real estate

professionals, and does not allow sublicensing.

In 2019, CoStar ( CSGP ) obtained a $500 million judgment against the

bankruptcy estate of real estate listing platform Xceligent over

the publication of 38,489 copyrighted photos, court records

show. Xceligent had filed to liquidate two years earlier.

CoStar ( CSGP ) threatened to sue Realtor.com and Redfin if they do

not remove its copyrighted photos.

Redfin declined to comment. Realtor.com did not immediately

respond to a request for comment.

The case is CoStar Group Inc ( CSGP ) et al v Zillow Group Inc ( ZG ) et al,

U.S. District Court, Southern District of New York, No.

25-06248.

(Reporting by Jonathan Stempel in New York; Editing by Chizu

Nomiyama and Emelia Sithole-Matarise)