Biological patent means a patent issued for an invention or discovery in biology. Such patents may be taken for the composition of matter, a procedure for obtaining or using one or more compositions, or for a product combining such things. In the U.S., natural biological substance itself may be patented. However, such substances must be sufficiently isolated from their naturally occurring states. Patents for adrenaline, insulin, and vitamin B12 are examples of patents issued for natural biological substances.