A Supplementary Protection Certificate (SPC) is a de facto extension of a patent (strictly speaking, it is actually a different right that gives similar protection to a patent) granted in respect of medicinal and plant protection products (e.g., pharmaceuticals, insecticides and pesticides). This additional form of IP is allowed because of the very long periods of time that drugs and chemicals may have to be trialled before they can be commercialised, which can eat significantly into the normal twenty year life of a patent.

A SPC is granted for a period of up to five years after expiry of the patent (with a six month extension for paediatric drugs).