Forensic software maker Guidance Software said it has signed an agreement to acquire Tableau, which develops and manufacturers computer forensic hardware, for $12.3 million.

Guidance is perhaps best known as the developer of Encase software, used to conduct computer investigations -- for responding to information security incidents, intellectual property theft, compliance audits or e-discovery requests -- while maintaining the forensic integrity of data.

Tableau, meanwhile, supplies forensic hardware, including write-blockers and forensic duplicators. Write-blockers enable investigators to maintain the integrity of hard drives they're examining by ensuring that they can only read -- not write -- data to the drives. Likewise, forensic duplicators provide a forensically sound way for investigators to copy data during an investigation. Tableau said it has sold more than 100,000 write-blockers to date.

Guidance's EnCase is considered to be the most widely used forensic software, competing with products from such companies as AccessData and Mandiant. According to Guidance, the product has over 30,000 licensed users and is used by more than half of the Fortune 50.

According to a statement from Guidance, "this acquisition extends Guidance Software's existing leadership in computer forensics technology by combining software with hardware for a complete forensic framework for the law enforcement, legal and corporate communities."

"Tableau is, by far, the leader in forensic hardware, and their products complement our industry-leading EnCase Forensic software," said Guidance's president and CEO, Victor Limongelli, in a statement. "Customers should benefit from a broadened product line addressing the complete forensic process."

The former president of Tableau, Robert Botchek, will oversee a newly created forensic business unit designed to develop new software and hardware products.

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