[JohnFen]

> How can they know/figure it out?

That's not a difficult problem, technically. There are a number of ways it can be done. Anything from comparing checksums to eFuses.

> Sure, but it's hidden from 99.99% of your user base

Yes. My point is that avoiding open sourcing firmware because of the risk of piracy or reverse-engineering doesn't make sense because pirates and/or interested engineers will do it directly from the devices anyway.

[brokenmachine]

>pirates and/or interested engineers will do it directly from the devices anyway

But they don't need to make it too easy by giving the source on a silver platter.