Reverse Engineering Techniques

It wouldn't be difficult for them to modify it to so was no longer like the original logo. If it was complicated it enough it might deter them but it would then become just as complicated to implement it. Although it might be possible to automate it. One of my ideas originally was sorta to "watermark" the board with a logo or text so that it was very difficult to see and existed on many scales but did not interfer with the circuit or was used part as part of the circuit. I suppose this wouldn't actually be too difficult but definitely would need to be automated.

An adulterated trademark is evidence of intentional deception. The courts are going to look dimly on such shenanigans. Not that the law is going to help you.

Manufacturers have used hidden structures and such to divert prying eyes, however it's a matter of cost to RE, not prevention. The easiest and cheapest method, as has been discussed here, is a combination of hardware and firmware with neither being manufactured by the same company. This won't be free, but it dies give some protection. Your best bet is still to sell a service that happens to have some hardware attached. Or engineer and sell fast enough to keep ahead of the copiers.

My favorite stunt when I ran the hybrid production line at Dickson Electronics was to introduce a new product exactly at the same time the copiers had finally figured out how to duplicate last year's version ;-) ...Jim Thompson

Sloman made Rodney Dangerfield a respected man, and world class EE by comparison.