Storage giant EMC is to buy document management vendor Documentum for $1.7bn.

EMC said that by incorporating its hardware with Documentum's content management software, customers will be able to better manage unstructured content, "from creation and use to archive and disposal".

Documentum's products fit well with the information lifecycle management technology EMC acquired earlier this year with its purchase of Legato, a storage-specific independent software vendor.

Both suites can be coupled with EMC hardware, and Documentum products have already been bundled with EMC's Centera, an ATA-based array that targets the market for fixed content.

Alan Pelz-Sharpe, US vice president at analyst Ovum, indicated that the announcement came as something of a surprise.

"An acquisition of Documentum is not in itself a surprise, as strong rumours have circulated the market regarding its impending [purchase], but the most likely suitor had appeared to be Oracle," he said.

"EMC is a storage vendor with no history of content or document management. It is hoped that Documentum will be allowed to continue largely as a subsidiary rather than merged into the whole of EMC."

As with Legato, EMC wants to keep Documentum at arm's length in order for its software to maintain its hardware-independent status and remain available for use on other vendors' kit.

"Documentum's sales, marketing and services will remain focused on selling and servicing Documentum's products and solutions," stated EMC.