TomoTherapy Inc.

Madison, Wis. • 608-824-2800 • www.tomotherapy.com

Exchange and Ticker: TTPY: Nasdaq

Filing Range: 10.20M shares @ $15.00 to $17.00

Offering Price: $19.00

Close on First Day: $22.67

Offering Size: $223.10M

Shares Outstanding: 48345337M

Underwriters: Merrill Lynch

Co-managers: Thomas Weisel Partners LLC/ Robert W Baird & Co. Inc./ William Blair & Co

Company Counsel: Michael Best & Friedrich

Manager Counsel: White & Case LLP

Auditor: Grant Thornton LLP

Market Capitalization on 5/31/07: $1091.64M

Close price at current month end: $22.58

DESCRIPTION

Develops precise radiation technology. The company’s technology will allow physicians to treat cancerous growths with less damage to healthy tissues around them. TomoTherapy’s machines will use tomography, or cross-sectional imaging, to deliver radiation precisely to parts of the body affected by cancer. TomoTherapy Inc. holds an exclusive license on 70 patents issued worldwide. Most of the patents are held and protected by the Wisconsin Alumni Research Foundation (WARF). The company continues to assist the University of Wisconsin in its research and evaluation of tomotherapy. Competitors include Varian Medical Systems Inc., Elekta AB, Siemens Medical Solutions, Accuray and BrainLAB AG.

VENTURE BACKERS

Advantage Capital Partners, Ascension Health Ventures LLC, Avalon Investments Inc., Baird Venture Partners, Endeavor Capital Management, Mayo Medical Ventures, Open Prairie Ventures, State of Wisconsin Investment Board, Venture Investors LLC.

Source: Thomson Financial