D. J. Bernstein

Software user's rights

In the United States, once you own a copy of a program, you can back it up, compile it, run it, and even modify it as necessary, without permission from the copyright holder. See 17 USC 117.

For example, after purchasing a copy of Microsoft Windows NT 4.0 Workstation---which is a poorly tuned version of NT 4.0 Server, minus a few utilities---you can back it up, apply a small patch that fixes the tuning, and run the result.

Microsoft hates this. Of course, Microsoft could restrict your rights by demanding that you sign a contract before you get a copy of Windows NT, but this would not do wonders for Windows sales.

So Microsoft puts a ``license'' on all of its software and pretends that you don't have the right to use the software unless you agree to the ``license.'' You can't patch Windows without their permission, according to the license; you can't use NT Workstation for more than 10 simultaneous connections; you must give Microsoft your first-born son. (Or something like that.)

The problem with Microsoft's license is that it's unenforceable. You can simply ignore it. Microsoft can't win a copyright infringement lawsuit: you own the software that Microsoft sold you, and Congress gave you the right to use it.

Ten years ago, the SPA convinced Louisiana to subvert the will of Congress by passing a law that declared shrinkwrap licenses enforceable. In Vault v. Quaid, 847 F.2d 255 (5th Cir. 1988), this law was struck down. Federal copyright law preempts state law.

The SPA didn't give up. It keeps arguing in court that, gee, if all these software makers claim that you can't use the software without a license, then they can't all be wrong, can they? (Ignore the fact that they're willingly selling their software to the public.)

The SPA lost again in Step-Saver but then won in ProCD. I expect the Supreme Court to step in within the next few years to resolve the dispute in favor of Vault and Step-Saver.


According to the CONTU Final Report, which is generally interpreted by the courts as legislative history, ``the right to add features to the program that were not present at the time of rightful acquisition'' falls within the owner's rights of modification under section 117.

Note that, since it's not copyright infringement for you to apply a patch, it's also not copyright infringement for someone to give you a patch. For example, Galoob's Game Genie, which patches the software in Nintendo cartridges, does not infringe Nintendo's copyrights. ``Having paid Nintendo a fair return, the consumer may experiment with the product and create new variations of play, for personal enjoyment, without creating a derivative work.'' Galoob v. Nintendo, 780 F. Supp 1283 (N.D. Cal. 1991), affirmed, 22 U.S.P.Q.2d 1587 (9th Cir. 1992). See also Foresight v. Pfortmiller, 719 F. Supp 1006 (D. Kan. 1989).

Free software

What does all this mean for the free software world? Once you've legally downloaded a program, you can compile it. You can run it. You can modify it. You can distribute your patches for other people to use. If you think you need a license from the copyright holder, you've been bamboozled by Microsoft. As long as you're not distributing the software, you have nothing to worry about.

Other countries

The European Software Directive (adopted by the UK in 1992) gives users the freedom to copy, run, modify, and reverse-engineer lawfully acquired programs.