Mobile Commerce Framework, an obscure company has sued Yelp and Groupon over a mobile commerce patent. The same company filed a similar patent infringement suit against Foursquare earlier.
The patent involved, US Patent No. 7,693,752 issued by the USPTO and keeping up with it's ambigious patent award, is something that we are again left to wonder about, who reads these patents before being awarded.
The Mobile Commerce Framework is represented by the owner of x-patents.
The case documents and other information at PriorSmart.com, Groupon, Yelp.