I would like to see that court case. It seem to me it would be fair game to refer to your software as Apache license 2 + XYZ Clause as long as you make clear that XYZ Clause is not part of the Apache 2 license.
It’s generally not against trademark law to refer to a combination of things. I can say that I use Microsoft Windows + Adobe Photoshop, as long as I don’t claim that Photoshop is part of Microsoft Windows, no trademark confusion will result.
What might get you in trouble is to modify the Apache license text itself to add an additional clause in the middle somewhere, or to call that modified version it “Apache 2 licensed” without any qualification.
It’s generally not against trademark law to refer to a combination of things. I can say that I use Microsoft Windows + Adobe Photoshop, as long as I don’t claim that Photoshop is part of Microsoft Windows, no trademark confusion will result.
What might get you in trouble is to modify the Apache license text itself to add an additional clause in the middle somewhere, or to call that modified version it “Apache 2 licensed” without any qualification.