<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE CONSOLIDATED STATEMENTS OF OPERATIONS FOUND ON PAGES F2 AND F3 OF QUIDEL'S FORM 10-K FOR THE YEAR-TO-DATE, AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-START> APR-01-1999 <PERIOD-END> DEC-31-1999 <CASH> 4,672 <SECURITIES> 0 <RECEIVABLES> 13,479 <ALLOWANCES> 1,604 <INVENTORY> 8,327 <CURRENT-ASSETS> 25,339 <PP&E> 21,207 <DEPRECIATION> 11,096 <TOTAL-ASSETS> 68,040 <CURRENT-LIABILITIES> 12,856 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 24 <OTHER-SE> 43,731 <TOTAL-LIABILITY-AND-EQUITY> 68,040 <SALES> 38,934 <TOTAL-REVENUES> 42,241 <CGS> 19,959 <TOTAL-COSTS> 42,695 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 213 <INCOME-PRETAX> (645) <INCOME-TAX> 0 <INCOME-CONTINUING> (645) <DISCONTINUED> 0 <EXTRAORDINARY> (891) <CHANGES> 0 <NET-INCOME> (1,536) <EPS-BASIC> (0.06) <EPS-DILUTED> (0.06)