This is an area where proprietary software has a huge advantage over open source. If you can't see the code in the first place, it's hard to claim it infringes on yours unless it visibly does almost exactly the same thing in almost exactly the same way. And even then, if you can't legally get ahold of a copy of the source code, it's hard to come up with a decent infringement case unless you have a patent on the exact functionality the other party is using.
The developers have no money, so let's sue the users
If a proprietary software company called Macrohard believes a company called Mickeysoft is using its code, it sues Mickeysoft. Presumably both companies sell this code either as a custom or packaged software product, and both derive substantial income from it. Macrohard can legitimately go to court and ask for a share of Mickeysoft's profits from that software, which in this illustration we'll call "Ventanas." If Macrohard wins, chances are Mickeysoft can still sell Ventanas, but Macrohard gets a cut of the profits. Life goes on.
But what if a group of free software developers create a piece of software called "Puertas" that has similar functionality to Ventanas? Even if most members of the group work for large companies, the group itself -- which we'll call the Pima Foundation -- probably doesn't have a large enough treasury to be worth a lawsuit. The next step, in our current poisonous techno-legal environment, is for Macrohard to sue companies and individuals that use Puertas.
This is like a musician whose work has been plagiarized suing people who bought the plagiarized song. What a stupid idea! The people listening to the music did nothing wrong. They didn't create or modify it. They just played it. That a lawsuit against software users who acted in similar good faith can even get into a courtroom shows how insane the modern concept of "intellectual property" has become.
Lawsuit threats as a marketing tactic
This is a truly despicable use of our legal system. In theory, software users choose programs based on a combination of price, utility, stability, and support. If you rely on programs that are only available for Windows, that is your operating system choice. If you believe Mac OS is better for your purposes, you buy Macs. If you believe Linux will fill your needs adequately -- and despite Microsoft's recent TCO jawboning you realize that Linux costs much less than the other two major OS choices -- you go with Linux.
Now imagine a marketing campaign that says you or your company might get sued if you use Linux or other popular free software. The fact that the suit probably has no merit doesn't take away from the fact that it could still be costly in both lawyer-fee money and your own time. This is the awful downside of dealing with the legal system: Even if you "win" against a nasty plaintiff who has no legitimate case, you lose.
Free software is especially vulnerable to this marketing tactic because groups like the putative Pima Foundation mentioned above typically put out their software with disclaimers that put all responsibility for the software on its users, which is certainly fair, considering that they aren't charging for it. Commercial software companies may try to duck all responsibility for their code with cleverly written End User License Agreements (EULAs), but we have laws that won't let them duck all responsibility, including that of making sure the code included in their products is legitimately theirs to sell.
Back to our made-up companies: Macrohard itself doesn't need to sue the Pima Foundation over its Puertas software product. A failed PR executive who adds a few lines of code to Puertas and then sues -- or threatens to sue -- other Puertas users accomplishes Macrohard's goal of turning potential users away from Puertas and, presumably, toward its own product. A down-the-tubes software company that claims Puertas was based on a product over which it has a shaky ownership claim and over which it sues Puertas users has the same effect, no matter how bogus its claims may be.
Obviously, it would be commercially advantageous for Macrohard to encourage these third-party lawsuits and threats. It would be a nasty tactic that crossed most ethical boundaries, but in a world where stock price and executive compensation are the only measures of a company's success, and "ethics" is a word used only by wishy-washy liberals who don't understand modern dog-rip-dog-to-shreds economics, there are companies that will stoop to this sort of thing, especially if they fear that free and open source software will eventually destroy their entire business model.
What can we do about this problem?
So far, it looks like the best thing NewsForge and other media that cover free and open source software can do is work hard to expose fraudulent legal attacks and keep a sharp eye out for ties between those who bring them and those who indirectly benefit from them. You can help by sending us any evidence you find of this behavior.
What we can all do is -- obviously -- not patronize companies that use legal blackmail as a marketing tactic, and urge friends to boycott them as well.
We can also pay more attention to the legal implications of the code we write or use, and generally spend more time learning how the legal system works. Yes, this means we spend less time working or playing with new technologies, but in today's legal and business climate we don't seem to have much choice.