As pointed out by others, this isn't really a contradiction. "Commercial" here is being used in a literal sense, not as a euphemism for "proprietary," because t

As pointed out by others, this isn't really a contradiction. "Commercial" here is being used in a literal sense, not as a euphemism for "proprietary," because the inquiry is about fiscal law, not about copyright law. Simply put, government acquisitions functions differently for build, buy (specialized), or buy-off-the-economy. How the DoD looks at buy-or-build as stewards of the taxpayers' money is not too dissimilar to how a startup might look at the tradeoffs of buy-or-build as stewards of investors' money. If your startup needs, say, a webserver, the buy-or-build question has a lot of freedom software, much of it no-cost, on the "buy" side of the question. Through that lens, I don't think it's a stretch to think of NGINX as "commercial off-the-shelf software." Neither does the DoD. And likely, neither does most of HN.