Patents back in the 1970s were only slightly broken compared to today. I've met several inventors or their relatives who invented things like milk cartons and every-day items we now take for granted. Up through the 1970s, "inventor" was a potential career path.
That all changed rapidly starting in 1982, when Congress voted to give all patent appeal cases to a single appeals court in Washington DC. This court basically created the patent troll industry. Before 1982, trolls would have been thrown out of court. Since then, this court has become a puppet to the patent troll industry through something called regulatory capture.
I wont go into the evils of software patents here. It is a regular flame topic on slashdot. However, we can blame this appeals court for them. Most recently, I was shocked when they changed long standing precident and declared that APIs are copyrightable, which if upheld, has potential to end software development as we know it.
I have several software patents. We are required to get them for defensive purposes. This is essentially a lawyer's tax on the software industry, with zero benefit to non-lawyers, so far as I can tell.