Harvard Journal of Law and Technology – Using a Competitor’s Trademark as a Keyword for AdWords is Not Trademark Infringement:
The United States Court of Appeals for the Tenth Circuit held that the use of a competitor’s trademark as a keyword that activates sponsored links in Google’s search engine is not trademark infringement. 1-800 Contacts, Inc. v. Lens.com, Inc., No. 11-4114, -4204, -4022 (10th Cir. July 16, 2013). The court affirmed the lower court’s summary judgment to defendant Lens.com with respect to 1-800 Contacts’ claim that Lens.com was directly liable for misdirecting customers to click on links to Lens.com after searching for the phrase “1-800 Contacts.” Id. at 4.
That’s what a court found, which isn’t to say that Google has to have the same rules. After this 2013 court ruling, Google changed their policy. Now they allow trademarked terms for keywords. They still block at least some trademarked terms from being used in the text of the ads depending on the usage, and trademark holders can file a complaint.