<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM MAXYGEN,
INC.'S QUARTERLY REPORT ON FROM 10-Q FOR THE PERIOD ENDED JUNE 30, 2000 AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
<CASH> 213,923
<SECURITIES> 9,995
<RECEIVABLES> 6,087
<ALLOWANCES> 0
<INVENTORY> 0
<CURRENT-ASSETS> 231,156
<PP&E> 6,804
<DEPRECIATION> 1,596
<TOTAL-ASSETS> 284,586
<CURRENT-LIABILITIES> 10,519
<BONDS> 0
0
0
<COMMON> 3
<OTHER-SE> 270,361
<TOTAL-LIABILITY-AND-EQUITY> 284,586
<SALES> 0
<TOTAL-REVENUES> 11,569
<CGS> 0
<TOTAL-COSTS> 0
<OTHER-EXPENSES> 27,944
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 108
<INCOME-PRETAX> (9,984)
<INCOME-TAX> 0
<INCOME-CONTINUING> (9,984)
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> (9,984)
<EPS-BASIC> (0.34)
<EPS-DILUTED> (0.34)
</TABLE>