June 24, 2007

Dear Colleagues,

We are pleased to announce that on June 18, 2007, NimbleGen signed a contract under which Roche has agreed to acquire 100% of the shares of NimbleGen. We believe this development is in the best interests of our customers, employees and shareholders. We will be joining one of the world’s leading healthcare companies, and one of the leading suppliers of life science research products.

As you know, NimbleGen has been growing rapidly over the past few years, and the Company had been in the process of preparing for an IPO to secure the financing needed to support our continued growth. As part of Roche, NimbleGen will have access not only to the financial resources to further develop the potential of our technology, but also to a world-class life sciences marketing, sales and support network, as well as an opportunity to leverage synergies based on a number of complementary products and technologies already sold by Roche in the genomics markets.

We expect this transaction to close before the end of the third quarter. After the close, NimbleGen will continue to operate as a distinct entity under the same name, but as part of the Roche Applied Science business area. We expect to conduct business as usual up until the close, and you can expect to receive similar if not improved service and support going forward. Roche plans to retain all of NimbleGen’s employees, and to continue operating out of NimbleGen’s various existing sites.

We are expecting no disruption to our business plans as a result of this transaction. From our customers’ perspective, there should be no change noticed, aside from the fact that NimbleGen will now have the financial resources to move even more rapidly in developing new products you need, and in continually improving the way in which we market, sell, support and service our products.

This is a very exciting time for us, and we look forward to continuing to work with you in advancing your research.

Sincerely yours,

Stan

Stanley D. Rose, Ph.D.
President & CEO
NimbleGen Systems, Inc.

About NimbleGen Systems, Inc.
For more information about NimbleGen, please visit the company’s website at www.nimblegen.com.