<TABLE> <S> <C>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM OPTIMARK
HOLDINGS, INC. AND SUBSIDIARIES UNAUDITED CONDENSED CONSOLIDATED FINANCIAL
STATEMENTS AT JUNE 30, 2000 AND FOR THE SIX MONTHS ENDED JUNE 30, 2000, AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-END> JUN-30-2000
<CASH> 22,505,711
<SECURITIES> 0
<RECEIVABLES> 1,897,803
<ALLOWANCES> 0
<INVENTORY> 0
<CURRENT-ASSETS> 28,531,154
<PP&E> 28,112,223
<DEPRECIATION> 11,931,859
<TOTAL-ASSETS> 82,561,415
<CURRENT-LIABILITIES> 15,224,311
<BONDS> 0
0
227,221
<COMMON> 366,121
<OTHER-SE> 64,047,709
<TOTAL-LIABILITY-AND-EQUITY> 82,561,415
<SALES> 0
<TOTAL-REVENUES> 6,105,462
<CGS> 0
<TOTAL-COSTS> 19,465,600
<OTHER-EXPENSES> 31,355,235
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 513,932
<INCOME-PRETAX> (44,008,470)
<INCOME-TAX> 0
<INCOME-CONTINUING> (44,008,470)
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> (44,008,470)
<EPS-BASIC> (1.20)
<EPS-DILUTED> (1.20)
</TABLE>