Nothing? Well, nothing except the remuneration he was entitled to receive in return for your being allowed to use his intellectual property.

I think that counts for something...

What I meant is, you deprive him of nothing which he already owns. No doubt he expects to be richer after enforcing his copyright and/or patent. But a cutpurse expects to be richer after lifting your wallet: the entire issue here is whether current copyright and patent legislation creates expectations in the copyright or patent holder which it is moral for him to act upon.

Peter

P.S. "Intellectual property" is another expression, like "piracy", which seeks to prejudge the entire point we're debating here, by (IMO artificially) treating intangibles as if they were (physical) property. It is misleading to use that expression.