<ARTICLE>                     5
<LEGEND>
                                   EXHIBIT 27

            INTERDIGITAL COMMUNICATIONS CORPORATION AND SUBSIDIARIES

                             Financial Data Schedule
                                   (Unaudited)
</LEGEND>


<MULTIPLIER>     1,000

                                 
<PERIOD-TYPE>                                                     9-MOS
<FISCAL-YEAR-END>                                             DEC-31-1998
<PERIOD-END>                                                  SEP-30-1999
<CASH>                                                             16,669
<SECURITIES>                                                       63,659
<RECEIVABLES>                                                       6,171
<ALLOWANCES>                                                           74
<INVENTORY>                                                         3,435
<CURRENT-ASSETS>                                                   93,140
<PP&E>                                                             24,588
<DEPRECIATION>                                                     16,951
<TOTAL-ASSETS>                                                    114,844
<CURRENT-LIABILITIES>                                              12,614
<BONDS>                                                             2,667
<PREFERRED-MANDATORY>                                                   0
<PREFERRED>                                                            10
<COMMON>                                                              486
<OTHER-SE>                                                         99,067
<TOTAL-LIABILITY-AND-EQUITY>                                      114,844
<SALES>                                                             2,022
<TOTAL-REVENUES>                                                   58,307
<CGS>                                                               4,002
<TOTAL-COSTS>                                                      32,817
<OTHER-EXPENSES>                                                    1,213
<LOSS-PROVISION>                                                        0
<INTEREST-EXPENSE>                                                    250
<INCOME-PRETAX>                                                    28,170
<INCOME-TAX>                                                        2,822
<INCOME-CONTINUING>                                                25,348
<DISCONTINUED>                                                          0
<EXTRAORDINARY>                                                         0
<CHANGES>                                                               0
<NET-INCOME>                                                       25,348
<EPS-BASIC>                                                         .52
<EPS-DILUTED>                                                         .52