Armijn Hemel, 32, lives with his parents in Tiel, a town in the middle of the Netherlands. He works as a technology consultant but spends several hours a week on his avocation: pestering some of the most powerful consumer electronics and technology companies in the world.
Mr. Hemel serves as a volunteer watchman for free, open-source software like the Linux operating system, which competes with Microsoft Windows. The use of free software has exploded, particularly in gadgets as varied as exercise bikes, energy meters and smartphones. Companies like Google and Sony often choose to piggyback on the work of others, rather than go through the ordeal of building all of the software for their products from scratch.
The problem that Mr. Hemel and others have stumbled upon is that some companies, even some technology-savvy ones, may be violating the rather easy-to-follow requirements associated with free software licenses. Typically, violations include tweaked versions of a free software product made available to the public or a failure to give credit to the original developers.
Last month, for example, Dell found itself in trouble. The company received a cease-and-desist letter from Mr. Hemel for shipping its new Streak tablet without providing the underlying open- source software code. Dell representatives acknowledged the issue and put the code on a Web site. “We are committed to fulfilling all of our obligations when using open-source code in our product,” a Dell spokesman said in a company blog.
Mr. Hemel says companies should make sure they know the ins and outs of everything they sell. “If we all play by the rules, we can make some really good stuff,” he said.
Quite often, companies that fail to live up to these requirements do so out of ignorance about the rules of engagement. Nonetheless, they become exposed to lawsuits.
For the moment, companies with…