....Given that willfulness requires an intent to infringe, or at least constructive knowledge of infringement plus a reckless disregard of the victim's rights, a finding of willfulness may be precluded if the defendant acted with a good-faith belief that he was not infringing.
.....
other factors may be relevant to finding an absence of "willfulness":
■Evidence of the defendant's good-faith belief that his conduct was lawful, coupled with rational attempts to comply with the copyright law as supposedly understood by the defendant.[27]
■Acting pursuant to legal counsel, even if the advice was erroneous, if the defendant disclosed all relevant cir stances to his attorney and followed the attorney's advice in good faith.[28]
http://itlaw.wikia.com/wiki/Willfulness