Software patents are probably unenforceable in most cases, at least in the US and Europe, are essentially unenforceable. The European Patent Office, very sensibly, denies software patents.
The USPTO has a strange insistence on granting them even though they aren't legally valid. Therefore, if you have a lot of money, you might file a software patent for one of four reasons:
1) You hope that the US courts might one day change their minds and start enforcing software patents.
2) You hope that you might scare people in to giving you licensing fees even though you know the patent won't be enforced.
3) You want to prevent others from scaring you in to giving them licensing fees.
4) You want to get a patent because it's impressive/looks good on your resume.
The USPTO has a strange insistence on granting them even though they aren't legally valid. Therefore, if you have a lot of money, you might file a software patent for one of four reasons:
1) You hope that the US courts might one day change their minds and start enforcing software patents.
2) You hope that you might scare people in to giving you licensing fees even though you know the patent won't be enforced.
3) You want to prevent others from scaring you in to giving them licensing fees.
4) You want to get a patent because it's impressive/looks good on your resume.