The only jurisdiction in the world that allows pure software patents is the U.S., and they have fallen into disfavour. They're very expensive to prosecute as well.
Software is primarily protected through copyright. You keep your source code secret. You don't let people see how your algorithm is structured and how the software is working, and you can commercialize those products with safety behind the copyright protection, keeping your source code secret. It's almost like know-how.
The software world moves so fast. A patent can take up to five years to issue, in some cases. In that space, the IT and software world, five years is yesterday's news, so there's not much point in investing in those kinds of patent applications. They're not really a good time effort. You really want to get first-mover advantage with software. Get it out there, commercialized, get product traction, get eyeballs, hits on web pages, etc., and source code copyright protection is more than adequate to provide companies proprietary advantage with software.