The U.S. Patent Law has been amended to deprive a patentee of its infringement remedies (to civil trial, injunction, damages and attorney's fees) where a medical practitioner or a related healthcare entity performs a patented medical activity. The statute defines medical activity as:

A related healthcare entity is an entity such as a hospital, health maintenance organization or nursing home with which the medical practitioner has a professional affiliation. The term "body" has been defined as a human body, organ, or cadaver or a non-human animal used in medical research or instruction directly relating to the treatment of humans. The term "patented use of a composition of matter" does not include a claim for a method of performing a medical or surgical procedure on a body that recites the use of a composition of matter where the use of that composition of matter does not directly contribute to achievement of the objective of the claimed method. This amendment was enacted in response to the outcry that ensued when a surgeon who had obtained a patent for "no stitch" cataract surgery tried to license the procedure for $4 per operation. This amendment does not apply to any patent issued before September 30, 1996.