A more thorough explanation:

An implied license by conduct is a type of license that arises from a property owner's conduct regarding another person's use of the property, even though the owner has not expressly consented to the property's use. This license is royalty-free and arises from the circumstances surrounding the conduct that give rise to an affirmative grant of consent or permission to infringe a patent's claims.

For example, if a patentee encourages the manufacture of infringing products, it may constitute an implied license to use the patent. Another example is when a patentee authorizes the sale or express grant of a license to a buyer, who then resells the license to a third party; the third party is the patentee's implied licensee.

Overall, an implied license by conduct is a permission that is not explicitly granted but is inferred from the actions of the property owner.