Software patents are still a threat. When you publish your software code, a company or a patent troll might file a patent for the inventions in your code. The patent offices should not grant patents for existing knowledge ('prior art'), but they will have a very hard time to find the ideas in your code. As such the troll might succeed in getting the patent, and might stop you and everyone else from further exploitation of your ideas.

Patents are a classical protection against patents, but it's an expensive and overly offensive solution. Defensive publications are another solution. But this concept is not well known and doesn't get a lot of recognition. The established implementations are commercial, have a per page publication fee and hide the defensive publications behind a paywall. The Defensive Publications program, a component of Linux Defenders, uses such commercial channel, but waives the publication fee and republishes openly outside the paywall. This solution is however for a very narrow (Free software) field and lacks the popularity it deserves.

The Open Patent Office is a non-profit organization that aims to stimulate innovation by providing an open, free and social alternative to the traditional patent offices. It allows inventors to register their innovative ideas as open patents. Open patents act as defensive publications. The Open Patent Office publishes these descriptions, timestamps them, gives them an open patent number, classifies them, facilitates discussion and facilitates easy searching and finding by patent examiners and the general public.