Microsoft has bought non-exclusive licences to Finjan Software's security code, and has become a minority shareholder in the company.

Finjan's content management software analyses the behaviour of computer code and blocks any action by a user that violates an enterprise security policy.

It is similar to the heuristic technology used by modern antivirus software to identify virus activity as it happens.

"What we have licensed is the set of patents on which our technology is based," said Asher Polani, chief executive at Finjan.

"Microsoft is a good example of a major company which understands the value of our technology. Down the road you'll hear some additional news on this."

The deal will not affect Finjan's own product range.