<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY  FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED FINANCIAL STATEMENTS OF CMGI, INC. FOR THE QUARTER ENDED OCTOBER
31, 1999 AS SET FORTH IN ITS FORM 10-Q FOR SUCH QUARTER AND FOR THE QUARTER
ENDED OCTOBER 31, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                          JUL-31-2000
<PERIOD-START>                             AUG-01-1999
<PERIOD-END>                               OCT-31-1999
<CASH>                                         705,001
<SECURITIES>                                 1,776,641
<RECEIVABLES>                                   98,418
<ALLOWANCES>                                         0
<INVENTORY>                                     17,650
<CURRENT-ASSETS>                             2,626,774
<PP&E>                                          99,335
<DEPRECIATION>                                       0
<TOTAL-ASSETS>                               5,431,682
<CURRENT-LIABILITIES>                          945,136
<BONDS>                                              0
<PREFERRED-MANDATORY>                          413,511
<PREFERRED>                                          0
<COMMON>                                         1,187
<OTHER-SE>                                   3,438,708
<TOTAL-LIABILITY-AND-EQUITY>                 5,431,682
<SALES>                                        123,731
<TOTAL-REVENUES>                               123,731
<CGS>                                          108,173
<TOTAL-COSTS>                                  108,173
<OTHER-EXPENSES>                               290,085
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                5700
<INCOME-PRETAX>                              (158,147)
<INCOME-TAX>                                  (40,735)
<INCOME-CONTINUING>                          (117,412)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                 (117,412)
<EPS-BASIC>                                     (1.08)
<EPS-DILUTED>                                   (1.08)