[nroman]

Companies that actually build things have two enemies when it comes to patent warfare. The first is competing companies that also build stuff. The best defense against them is obtaining a large patent trove. This creates a mutually assured patent destruction situation, shielding the company from competitors' patents.

The second enemy is patent trolls. They don't actually build anything, so defensive patents are useless.

Because of this, the most prudent thing for a company to do is aggressively acquire patents with one hand, and lobby for the abolishment of these patents with the other hand.