Thousands of dollars, except per-share amounts and numbers of shares

On July 1, 2004, the Company acquired all of the outstanding equity interests in Atto Bioscience, Inc., a privately-held company specializing in optical instrumentation, software, and reagents for real-time analysis of interactions taking place in living cells. The purchase price was approximately $25,800 in cash. The purchase price has been allocated to assets acquired and liabilities assumed based on estimated fair values as follows:

     In connection with this acquisition, a charge of $1,100 was recorded in connection with purchased in-process research and development. The results of operations of the acquired company were included in the consolidated results of the Company from the acquisition date. Unaudited pro forma consolidated results, after giving effect to this acquisition, would not have been materially different from the reported amounts for 2004.