Eben Moglen: "The GPL Is Enforcable"

"[I]t is sometimes said that the GPL can't be enforced because users haven't 'accepted' it.

This claim is based on a misunderstanding. The license does not require anyone to accept it in order to acquire, install, use, inspect, or even experimentally modify GPL'd software. All of those activities are either forbidden or controlled by proprietary software firms, so they require you to accept a license, including contractual provisions outside the reach of copyright, before you can use their works.

The free software movement thinks all those activities are rights, which all users ought to have; we don't even want to cover those activities by license. Almost everyone who uses GPL'd software from day to day needs no license, and accepts none. The GPL only obliges you if you distribute software made from GPL'd code, and only needs to be accepted when redistribution occurs. And because no one can ever redistribute without a license, we can safely presume that anyone redistributing GPL'd software intended to accept the GPL. After all, the GPL requires each copy of covered software to include the license text, so everyone is fully informed.

Despite the FUD, as a copyright license the GPL is absolutely solid. That's why I've been able to enforce it dozens of times over nearly ten years, without ever going to court."

Eben Moglen, writing at Free Software Foundation's Web site , September 10, 2001

Bruce Perens: "Free Software Leaders Stand Together"

"Although Microsoft raises the issue of GPL violations, that is a classic red herring. Many more people find themselves in violation of Microsoft licenses, because Microsoft doesn't allow copying, modification, and redistribution as the GPL does. Microsoft license violations have resulted in civil suits and imprisonment. Accidental GPL violations are easily remedied, and rarely get to court.

It's the 'share-and-share-alike' feature of the GPL that intimidates Microsoft, because it defeats their 'embrace and extend' strategy. Microsoft tries to retain control of the market by taking the result of open projects and standards, and adding incompatible Microsoft-only features in closed-source. Adding an incompatible feature to a server, for example, then requires a similarly-incompatible client, which forces users to "upgrade". Microsoft uses this deliberate-incompatibility strategy to force its way through the marketplace. But if Microsoft were to attempt to 'embrace and extend' GPL software, they would be required to make each incompatible 'enhancement' public and available to its competitors. Thus, the GPL threatens the strategy that Microsoft uses to maintain its monopoly.

Microsoft claims that Free Software fosters incompatible 'code forking,' but Microsoft is the real motor of incompatibility: they deliberately make new versions incompatible with old ones, to force users to purchase each upgrade. How many times have users had to upgrade Office because the Word file format changed? Microsoft claims that our software is insecure, but security experts say you shouldn't trust anything but Free Software for critical security functions. It is Microsoft's programs that are known for snooping on users, vulnerability to viruses, and the possibility of hidden 'back doors.'"

Bruce Perens, writing at his personal Web site 

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