Intrinsic evidence consists of the patent documentation and any prosecution history of the patent.

Extrinsic evidence is testimony, expert opinion, or other unwritten sources; extrinsic evidence may not contradict intrinsic evidence.

Trezise finds the intrinsic evidence "remarkable," but cautions that no written or reported evidence suggests that Debussy consciously sought such proportions.

The brief argues that in construing patent claims a court should primarily rely on a patent's intrinsic evidence (its description of the invention and its prosecution history) rather than dictionaries and other external sources.

In a triumph of early modern hermeneutics, the Italian humanist Lorenzo Valla proved in 1440 that the "Donation of Constantine" was a forgery, through intrinsic evidence of the text itself.

For the author of these maxims acknowledges, by a play on words (ho hesychias pheronymos), that his name is Hesychius and that he is a Basilian monk; furthermore a number of manuscripts support this intrinsic evidence.