In 1989, Apple's look and feel lawsuit against Microsoft brought the idea of interface copyright to the attention of the programming community. Apple was trying to claim a monopoly over a broad class of graphical user interfaces. If Apple succeeded, not only Microsoft, but every software developer, would be legally compelled to design gratuitously incompatible software.
Sorry, no gifs due to patent problems.
In response, John Gilmore and Richard Stallman together commissioned the design of the "fanged Apple"–a button showing the Apple logo with vicious teeth. This was followed by an advertisement placed in The Tech, MIT's student newspaper, which in turn led to a protest rally at the HQ of Lotus Development Corporation--another "look and feel" lawsuit plaintiff.
The enthusiastic response to the first protest led to the formation of the League for Programming Freedom in late 1989.
The general aim of the League for Programming Freedom is to prevent monopolies on software development. Initially the League's only specific position was against interface copyright. But once the League began to operate, members called its attention to the problem of software patents.