If you haven't heard, Major League Baseball's lawyers shut down a website, obamaofdreams.com, which sold t-shirts based on teams' jerseys, with "Obama" substituted the team name (here's the full catalogue).
The frustrating part of this is that MLB, while it may have the legal right to assert its trademark, is shooting itself in the foot. The t-shirts are different enough from official MLB gear that it's hard to imagine them cutting into those sales; meanwhile, the shirts advertise not only the candidate but the baseball teams teams themselves, which is good for MLB. Also, for a sport that struggles to stay relevant among young people and African-Americans, why not to take the opportunity to be associated with a figure who has such cache among those groups? Meanwhile, MLB has asserted itself as the enemy of the guy who ran the company (Morris Levin, who describes himself as "a huge Phillies fan") and his potential customers, all of whom are baseball fans i.e. the people whose unconditional loyalty MLB's business depends upon.
Letting these sorts of infringements slide is not unprecedented; Tim Wu in Slate has noted "the growing category of 'tolerated use'—use that is technically illegal, but tolerated by the owner because he wants the publicity." It's too bad that MLB missed an opportunity to bank some goodwill with its fans and move its marketing style into the 21st century in the process.