In the US marketers may use competitors’ trademarks as keywords, so long as they don’t appear in the ad text itself. Previously Google used a more restrictive policy in the UK, not allowing use of competitors’ trademarks at all. Last month the company changed its UK rules to conform to the more liberal US policy.

Accordingly, UK marketers are promising to sue when the new policy is implemented. One legal expert interviewed about the change suggested that UK regulators will ultimately be compelled to step in to resolve the anticipated dispute.