Ask HN: How to protect yourself against patents from your own product?

Imagine a company that comes out with a great product with some interesting ideas, but nothing Earth-shaking, just a better combination of the known things.

A patent-troll realizes that the ideas were not patented, he files for the patents, receives them and sues the company a few years later for big money.

How can one possibly defend themselves from such scenario? (Let's suppose the company wouldn't like to spend money on their own patent-applications.)