General Public Virus n. Pejorative name for some versions of the GNU project copyleft or General Public License (GPL), which requires that any tools or apps incorporating copylefted code must be source-distributed on the same counter-commercial terms as GNU stuff. Thus it is alleged that the copyleft `infects' software generated with GNU tools, which may in turn infect other software that reuses any of its code. The Free Software Foundation's official position as of January 1991 is that copyright law limits the scope of the GPL to "programs textually incorporating significant amounts of GNU code", and that the `infection' is not passed on to third parties unless actual GNU source is transmitted (as in, for example, use of the Bison parser skeleton). Nevertheless, widespread suspicion that the copyleft language is `boobytrapped' has caused many developers to avoid using GNU tools and the GPL. Recent (July 1991) changes in the language of the version 2.00 license may eliminate this problem.