Roche purchases shares in tender offer for Ventana

Commences subsequent offering period

Roche (SWX: ROG.VX; RO.S; OTCQX; RHHBY) today announced that its wholly-owned subsidiary Rocket Acquisition Corporation has accepted for payment all shares validly tendered pursuant to its tender offer for all outstanding shares of common stock of Ventana Medical Systems, Inc. (NASDAQ: VMSI) at $89.50 per share in cash.

As of the expiration of the tender offer, a total of approximately 25,491,221shares of Ventana common stock were tendered and not withdrawn, representing approximately 70.5 % of Ventana’s outstanding shares.

Franz B. Humer, Roche Chairman and CEO said: “We are pleased that we have successfully completed this step in the transaction and look forward to welcoming Ventana to the Roche Group.”

Roche also announced that Rocket Acquisition is providing a subsequent offering period to permit shareholders who have not yet tendered their shares the opportunity to do so. This subsequent offering period will expire at 7:00 p.m., New York City time, on Friday, February 15, 2008. All shares tendered during the subsequent offering period will be purchased for the same cash consideration per share as was paid in the tender offer. Payment for such shares will be made promptly after the tender of the shares. Procedures for tendering shares during the subsequent offering period are the same as during the tender offer except that the guaranteed delivery procedures may not be used and withdrawal rights will not be available.

After expiration of the subsequent offering period, Roche will complete the acquisition of Ventana through a merger in which all shares of Ventana not owned by Roche and its subsidiaries (other than shares as to which appraisal rights are validly exercised) will be converted into the right to receive the same cash consideration per share as was paid in the tender offer. As a result of the purchase of shares in the offer, Rocket Acquisition has sufficient voting power to approve the merger without the affirmative vote of any other Ventana shareholder.

Greenhill & Co. and Citi are acting as financial advisors to Roche and Davis Polk & Wardwell is acting as legal counsel.