Starting March 1st, Yahoo will no longer allow competitor bids for keywords containing trademarks. The move is intended "to more easily deliver quality user experiences when users search on terms that are trademarks." Under the previous arrangement, ads would be approved if there was a competitive comparison and was somewhat objective and informative. Now according to Yahoo, "advertiser listings that qualify under the reseller or non-competitor information guidelines may be allowed, subject to Yahoo's discretion to accept or reject listings."
While it's obviously a move to protect themselves from litigation, it's a delayed move, but still a smart one. Most other pay-per-click providers have established guidelines on trademark bidding and have actively limited the practice for some time.
Google however, still allows trademark bidding.
The development will not directly affect any advertiser unless they are directly bidding on a search term that is trademarked. Most providers of pay per click solutions allow bidding on trademark terms if there is an obvious distribution (affiliate/partner) arrangement. Meaning that SportsMart can bid on the term Nike, but Adidas cannot.
yahoo, ysm, keywords, trademarks