Bradley M. Kuhn is the most prominent practitioner of gpl-copyleft-mechanism enforcement in the generation following stallman. He served as executive director of the free-software-foundation and later became president of the software-freedom-conservancy, which he helped found in 2006.
Kuhn worked with eben-moglen at the software-freedom-law-center before the Conservancy was established as a separate organization focused on fiscal sponsorship of free software projects and GPL enforcement. The Conservancy has pursued some of the most significant GPL enforcement litigation, building on the legal framework Stallman created with gpl-v1, gpl-v2, and gpl-v3.
His work represents the institutionalization of Stallman's vision: ensuring that copyleft is not merely a philosophical statement but an enforceable legal mechanism that upholds the four-freedoms in practice. This means actively pursuing companies that violate the gpl-copyleft-mechanism by distributing GPL-licensed software without providing corresponding source code.
Kuhn has been consistent in maintaining Stallman's distinction between software-freedom-vs-open-source, rejecting the pragmatic reframing of eric-raymond and the open-source-initiative in favor of the ethical framework of the free-software-definition. He co-authored with stallman the essay freedom-or-power, which articulates this philosophical commitment.
He appears in discussions of the gplv3-and-later-career-2006-present era and is a key figure in understanding how the free-software-foundation's enforcement mission has evolved.