A more thorough explanation:

Accelerated-reentry theory, also known as post-expiration-sales theory, is a legal concept used in patent law. It refers to a theory of lost-profits remedy where compensation is sought for sales lost after a patent has expired. This is based on the idea that infringement gave the competitor a head start on entering the market.

For example, if a company holds a patent for a new type of phone and a competitor starts selling a similar phone before the patent expires, the original company may seek compensation for the sales lost during that time. This is because the competitor had an advantage in entering the market due to their infringement of the patent.

The accelerated-reentry theory is used to ensure that patent holders are compensated for the full value of their invention, even after the patent has expired. It is an important concept in patent law and helps to protect the rights of inventors and companies who invest in research and development.