On 30 April 1993, CERN's Directors declared that the three components of Web software (the basic line-mode client, the basic server and the library of common code) that Tim Berners-Lee @timbl had first proposed in 1989, were to be put in the Public Domain.

We are grateful to CERN and to Tim for this world changing decision which has enabled the W3C community to create open, accessible, international web standards which make the web work, for everyone.
https://home.web.cern.ch/science/computing/birth-web/licensing-web