(nearly) None at all (Score 1)

Though it is hard to accept, pirates are better than us; they have to concentrate on a very small piece of code, while you are investing all your business on a lot of functionalities.

Invest in the quality of your software and of your support services; if the software is good, pirates will play your game: your software will go round and round, and you will save a lot of money in advertising.

You could also prevent piracy: just adopt a non-commercial free licence, so that you will push on the user responsibility; the more people uses your software, the more you save money in training and support, and more companies will feel confident with your product.

But, when a user calls for support, you can ask an installation code provided by the installed software, so that you can link the license to the customer. Then you can get money for problem solving, for a prompt response time for bug correction and patch and upgrade distribution, etc.

And you can always change your mind about DRM in the future: please remember that for a company the bigger cost is not to adopt a new software , but to switch from an existing to a new one: start as soon as possible to get new users, and do it before your competitors do.

Andy