https://www.epo.org/en/service-support/faq/searching-patents/patent-management-and-valuation/what-are-good-indicators

What are good indicators of patent value?

Research has identified a number of indicators that may be used to assess a patent's value.

The number of forward citations is often used as a strong indicator of patent value. A forward citation is a reference to the patent to be evaluated in a later document. An analysis of such citations produces a network of links called a patent citations network which is used in evaluation. The number of times a patent is cited indicates its scientific importance and therefore its value.

Other indicators of patent value include:

  • the patent family size
  • the lifespan of a patent
  • the outcome of oppositions to the patent application
  • the number and quality of claims

These factors or "value indicators" can influence the value of the patent both positively and negatively in the same way as factors such as location, numbers of rooms, nearby schools, etc. affect the value of a house.