MADISON, WIS.,— Cellular Dynamics International, Inc., a developer and manufacturer of fully functioning human cells in industrial quantities to precise specifications, today announced that it has commenced an initial public offering of 3,846,000 shares of common stock pursuant to a registration statement on Form S-1 filed with the U.S. Securities and Exchange Commission (“SEC”). In addition, the underwriters will have a 30-day option to purchase up to an additional 576,900 shares of common stock from the Company. The initial public offering price is currently expected to be between $12.00 and $14.00 per share of common stock.

The Company intends to use the net proceeds that it receives in the offering for research and product development activities; sales and marketing activities, including expansion of its sales force to support the ongoing commercialization of its products; property, plant and equipment, including the build-out of its laboratory in California, and intellectual property; and for working capital and other general corporate purposes.

J.P. Morgan Securities LLC is acting as sole book-running manager for the offering, and Cowen and Company, LLC and Leerink Swann LLC are acting as co-managers.

A registration statement relating to these securities has been filed with the SEC but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective.