Facebook Sues Startup Over Use Of Word ‘Book’ Facebook has filed a federal lawsuit against Teachbook, claiming that the use of the word “book” in the startup’s name infringes on the popular social network’s trademark. The complaint, filed last week in U.S. District Court in San Jose, Calif., claims the problem arises from the fact that Teachbook is a kind of social network for teachers, and is using “book” in its name to ride on Facebook’s coattails






