Or slightly randomly modify all the parameters on the copy you distribute, then it will be a match for nobody.

You compare all three and average the variance of each value. So the more copies the better.

...or just steal it so that even if it can be traced, it's not your problem.

In fairness to ipaddr, this can result in worse performance at this point.

OK, this is a fun game. I think your counterattack assumes I'm picking these million weights uniformly randomly among the 175 billion. I modify my original answer: s/a million/half the weights in a deterministic subset of 2 million weights/

Select the deterministic subset by just hashing some identifier for each weight.

For any reasonable number of copies, there's a pretty unique subset between all your copies sharing a large amount of bits flipped in the same direction among this subset.