The data storage company EMC says it has agreed to buy Isilon for $2.25 billion in cash.

It is offering $33.85 per share for the Seattle-based company, a 29 percent premium over Isilon Systems Inc.'s previous closing share price of $26.29.

EMC Corp. says Isilon will expand the breadth of products it can offer customers for storing big amounts of data involved in applications such as gene sequencing and streaming online video.

It says the boards of both companies have approved the deal and it expects to close the acquisition by year-end.

Isilon shares surged 18 percent in premarket trading after the New York Post first reported the deal.