First, I haven't met Nathan personally but from everything I see about him internal to Microsoft (from his time at the company) and his time outside, he is a very, very smart man. And quite rich. I think assigning simple labels like 'good' and 'evil' doesn't quite cut it.
My opinion/guess (with zero inside knowledge) is that Nathan doesn't really care about the patent side of the equation much. He just wants to do interesting ideas and get people in the room to dream up of (and sometimes build) cool stuff. Some of their work around nuclear power is super interesting for example. The patents are just a revenue stream for them to continue doing this.
"Nathan Myhrvold talks about a few of his latest fascinations -- animal photography, archeology, BBQ and generally being an eccentric genius multimillionaire."
My opinion/guess (with zero inside knowledge) is that Nathan doesn't really care about the patent side of the equation much. He just wants to do interesting ideas and get people in the room to dream up of (and sometimes build) cool stuff. Some of their work around nuclear power is super interesting for example. The patents are just a revenue stream for them to continue doing this.