A more thorough explanation:

The advice-of-counsel defense is a legal argument used in patent infringement cases. It involves the defendant claiming that they sought and relied on the advice of a lawyer before continuing with the allegedly infringing act.

For example, if a company is accused of infringing on a patent, they may argue that they consulted with a lawyer and were advised that their actions did not infringe on the patent. They may then use this advice as a defense against the infringement claim.

However, it's important to note that the advice-of-counsel defense is not a true defense. Instead, it is considered a factor in determining whether the infringement was willful, which can impact the amount of damages awarded to the patent owner.

Overall, the advice-of-counsel defense is a way for defendants to show that they acted in good faith and sought legal guidance before taking any potentially infringing actions.