Stallman bụ onye mbụ n'echiche nke copyleft, nke na-eji ụkpụrụ nke iwu nwebisiinka iji chekwaa ikike iji, gbanwee, ma kesaa ngwanrọ n'efu, ọ bụkwa onye edemede bụ isi nke ikikere ngwanrọ n'efu nke na-akọwa okwu ndị ahụ, ọkachasị GNU General Public License (GPL), ikikere ngwanrọ n'efu a na-ejikarị eme ihe. Na 1989, ọ kwadoro Njikọ maka nnwere onwe mmemme. Kemgbe etiti afọ 1990, Stallman ejirila oge ya na-akwado ngwanrọ n'efu, yana mkpọsa megide patent ngwanrọ, njikwa ikike dijitalụ (nke ọ kpọrọ njikwa mgbochi dijitalụ, na-akpọ okwu a na-emekarị), na usoro iwu na teknụzụ ndị ọzọ ọ na-ahụ dị ka iwepụ nnwere onwe ndị ọrụ. Nke a gụnyere nkwekọrịta ngwanrọ, nkwekọrịta na-ekpugheghị, nkwekọrịta na-arụ ọrụ, igodo, dongles, mbipụta, na koodu ikike ikike nwere ikike.
nkwekọrịta ikikere ngwanrọ, nkwekọrịta nzuzo, igodo mmeghe, dongles, mgbochi nnomi, usoro ikikere, na ọnụọgụ abụọ na-enweghị koodu isi