Jennifer Lawrence ..... Non-Selfie Nude Pics Create Legal Hurdle

Jennifer Lawrence's fight to get her hacked nude photos removed from the Internet might have hit a legal snag -- the same one Ellen DeGeneres ran into with that famous Oscars selfie.

Sources connected to the investigation tell TMZ ... Lawrence's attorney fired off a letter to a porn website demanding it take down the nude photos of J-Law because she owns the copyright on the pics. We're told the website isn't buying that argument though.

The site's stance is ... since some of the pics are NOT selfies, the person who actually took those photos would most likely hold the copyright. In its response to Lawrence's attorney ... we're told the site is demanding proof of Jennifer's copyright, or the name of the person who snapped the shots.

Ironically, J-Law was prominent in the Oscar selfie -- which became the most retweeted photo ever when Ellen posted it. But as we told you, Bradley Cooper actually owns the shot because he took it. FUN FACT: Bradley co-starred with J-Law in "Silver Linings Playbook."