Computer Associates has pledged 14 patents to the open source community.

From 1 August 2005 CA will not enforce its patents against software governed by software licences that are approved as open source as defined by the Open Source Initiative. 

The patents cover several elements of software design, including one that handles the translation between programming languages. They also cover storage and systems management technology. The full list has been published on CA's website here. 

CA said that the move was inspired by a similar initiative from IBM earlier this year, when the company pledged 500 patents to the open source community.

The two companies called on other vendors to join in creating a "patent commons", a pool of patents which are available royalty-free to developers and users.

Patent litigation is considered one of the biggest threats to open source software development.

A successful claim could initiate similar assertions to those made by SCO, which claims to own the copyrights for key elements of Unix and demands punitive damages and royalty payments from developers and end users.

Other vendors have pledged patents to the open source community, although some did so under different terms. Sun Microsystems, for instance, has offered 1,670 patents while Nokia tendered its full patent portfolio. 

But Sun's pledge is limited to software projects that fall under the Common Development and Distribution Licence. And Nokia is only supporting the Linux operating system, leaving over 4,000 other open source projects out in the cold.

In addition to the pledge, CA also revealed that it had signed a cross-licensing agreement with IBM that provides both firms with a licence to use each other's patents.