<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM ILLUMINA
INC.'S BALANCE SHEETS AS OF DECEMBER 31, 1999 AND SEPTEMBER 30, 2000 AND RELATED
STATEMENTS OF OPERATIONS AND CASH FLOWS FOR THE THREE MONTHS ENDED SEPTEMBER 30,
1999 AND 2000 AND FOR THE NINE MONTHS ENDED SEPTEMBER 30, 1999 AND 2000 AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<PERIOD-TYPE> 9-MOS 9-MOS
<FISCAL-YEAR-END> DEC-31-1999 DEC-31-2000
<PERIOD-START> JAN-01-1999 JAN-01-2000
<PERIOD-END> SEP-30-1999 SEP-30-2000
<CASH> 21,164,114 121,582,842
<SECURITIES> 11,924,163 2,585,799
<RECEIVABLES> 0 6,200,000
<ALLOWANCES> 0 0
<INVENTORY> 0 0
<CURRENT-ASSETS> 33,493,045 132,394,118
<PP&E> 296,286 2,409,870
<DEPRECIATION> (4,972) (284,739)
<TOTAL-ASSETS> 33,894,658 134,965,004
<CURRENT-LIABILITIES> 612,408 2,199,146
<BONDS> 0 0
<PREFERRED-MANDATORY> 0 0
<PREFERRED> 37,397,998 0
<COMMON> 51,391 319,394
<OTHER-SE> (5,417,139) 126,491,448
<TOTAL-LIABILITY-AND-EQUITY> 33,894,658 0
<SALES> 0 0
<TOTAL-REVENUES> 100,269 662,589
<CGS> 0 0
<TOTAL-COSTS> 1,644,578 6,044,871
<OTHER-EXPENSES> 0 0
<LOSS-PROVISION> 0 0
<INTEREST-EXPENSE> 0 0
<INCOME-PRETAX> 0 0
<INCOME-TAX> 0 0
<INCOME-CONTINUING> (1,479,120) (3,874,653)
<DISCONTINUED> 0 0
<EXTRAORDINARY> 0 0
<CHANGES> 0 0
<NET-INCOME> (1,479,120) (3,874,653)
<EPS-BASIC> (0.94) (0.19)
<EPS-DILUTED> (0.94) (0.19)