SAN FRANCISCO AP – The popular online social network Facebook Inc. is being sued by an Indiana woman who alleges it has profited from its members sending thousands of unauthorized text messages to mobile phone users whose numbers previously belonged to other people.

The lawsuit, filed Monday in a San Jose federal court, highlights the confusion and frustration that can arise as Web sites extend their services to mobile handsets with phone numbers that have been reassigned, or “recycled,” after another customer’s service ended.