Mr. Hemel serves as a volunteer watchman for free, open-source software like the Linux operating system, which competes with Microsoft’s Windows. The use of free software has exploded, particularly in gadgets as varied as exercise bikes, energy meters and smartphones. Companies like Google, TiVo and Sony often opt to piggyback on the work of others rather than going 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, these include making tweaked versions of a free software product available to the public, or simply giving credit to the original developers.