 As it is quite difficult to switch to another architecture, most researchers paid for a commercial license.Software was not considered copyrightable before the 1974 US Commission on New Technological Uses of Copyrighted Works (CONTU) decided that "computer programs, to the extent that they embody an author's original creation, are proper subject matter of copyright".Therefore, software had no licenses attached and was shared as public-domain software, typically with source code.