Pretty much any civil action is similar. Unless it's on a massive scale, ask a lawyer what you should do when someone appears intent on pushing a frivolous copyright suit on you. Sure, you have every right to use that content, but do you have the tens of thousands of dollars (minimum) and months or years in court to prove it? It's practically always easier to just accept that you've been bullied out of exercising your rights and replace the contested content with something that the claimant won't launch a frivolous suit over. Lawsuits are only worthwhile when the workaround is more expensive, which is often a hard standard to meet -- that's why most cases end in settlement.
