Yes, Bethesda is required to defend their trademark but suing the other party to completely change course isn't the only option available. See Trademark Coexis

Yes, Bethesda is required to defend their trademark but suing the other party to completely change course isn't the only option available. See Trademark Coexistance http://www.wipo.int/wipo_magazine/en/2006/06/article_0007.html http://www.wipo.int/wipo_magazine/en/2006/06/article_0007.ht... SparkFun vs SPARC International http://www.sparkfun.com/news/344 http://www.sparkfun.com/news/344