IBM and Watchfire announced on Wednesday that the companies has signed an agreement for Big Blue to buy the compliance and security audit firm.

The technology giant plans to merge Watchfire into its IBM Rational software group, according to a statement issued by the companies. Watchfire's core products include AppScan, which allows Web application developers to scan their code for vulnerabilities.

Watchfire "will further strengthen our ability to help customers mitigate risk by integrating security, quality testing and compliance testing requirements early in the software development process -- before vulnerabilities are exposed,” Danny Sabbah, general manager, IBM Rational software, said in a statement.

The purchase is IBM's latest acquisition in the security market. Last August, Big Blue bought up security product and service provider Internet Security Systems in a $1.3 billion deal. Financial terms of the latest deal were not disclosed.