<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM STATEMENT OF
OPERATIONS AND BALANCE SHEET AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH 10Q
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               SEP-30-1997
<CASH>                                          36,966
<SECURITIES>                                   124,855
<RECEIVABLES>                                    2,765
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                                     0
<PP&E>                                          20,405
<DEPRECIATION>                                (11,481)
<TOTAL-ASSETS>                                 173,510
<CURRENT-LIABILITIES>                            4,326
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                           182
<OTHER-SE>                                     169,002
<TOTAL-LIABILITY-AND-EQUITY>                   173,510
<SALES>                                              0
<TOTAL-REVENUES>                                15,949
<CGS>                                                0
<TOTAL-COSTS>                                 (23,775)
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                   0
<INCOME-PRETAX>                                (7,826)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                            (7,826)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                   (7,826)
<EPS-PRIMARY>                                    (.45)
<EPS-DILUTED>                                    (.45)