Groupon advertised on Google AdWords discounts not provided by this company, a travel services company from San Francisco claimed at a District Court in northern California.
San Francisco Comprehensive Tours company sued the Chicago’s discount coupons business managed by Andrew Mason because according to a story published by L.A. Times newspaper on March 23, 2011, Groupon ran paid search on Google to mislead customers looking for tours discount prices.
It seems that Groupon manipulated search engine optimization strategies to create ads that unfairly look like advertising displayed by other companies; San Francisco Comprehensive Tours among them.
Lawsuit document: http://www.documentcloud.org/documents/74768-sf-v-groupon