[ghaff]

The traditional meaning does seem to involve sales and many law firms seem to still use that definition. However, trademarks are widely used for upstream open source projects. Here's Google's take on the "use in commerce" phrase: https://google.github.io/opencasebook/trademarks/

ADDED: The disconnect isn't really that surprising. Historically, why would you trademark something if you had no intention of selling it? How would it even get broadly distributed if you were just giving something away? Obviously, those conditions don't necessarily apply today even though you have the same issues of confusing different goods and services that have always existed. As for the law firms, it's mostly an argument that if you want an IP lawyer in an open source context, you probably want one who actually has experience in the area.

[samtuke]

Good catch. To quote them: "the court rejected the argument that the lack of direct profit from releasing software under the GNU General Public License rendered the original Coolmail name unenforceable as a trademark, holding that distributing software for end-users over the Internet satisfies the “use in commerce” requirement."