Software hoarding

Software hoarding is the creation of proprietary software products based on free software code. This software forking can cause interoperability problems leading to vendor lock-in, as well as a limitation of knowledge. The practice of software hoarding was the impetus for the creation of copyleft. Software hoarding is legal unless restricted by copyleft or a similar license, but it is considered immoral by the more ideological proponents of free software.

The term was created by Richard Stallman in 1984 after the company Symbolics refused to provide him access to the extensions and improvements they had added to the public domain version of his Lisp interpreter he had given them.