Having never been much into electronics I got interested when the Arduino came out. But looking at the diagram I could see it was just an AMD chip with a handful of of passive components. I ordered a couple of the chips as through hole and set one up on a breadboard. I programmed it using the Arduino app, but hated that, so I set up without it, which wasn't much trouble.

When I discovered ESPs, the Arduino app seemed the only viable route but I found Platformio had a good solution.

All in all Arduino seems like an inspiration, without ever having been useful!

Did Arduino have any patents that were in some way useful to Qualcomm?

I can't think of any other reasons for them to be interested in a retail-facing company, with mostly educational products, like Arduino.

Honestly that's so far way from their usual stuff I'm expecting to find an "Our Incredible Arduino journey" blog post in a few years from now.