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THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE UNAUDITED FINANCIAL STATEMENTS OF NETWORK-1 SECURITY SOLUTIONS, INC. FOR THE PERIOD ENDED MARCH 31, 2000 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.

3-MOS DEC-31-2000 JAN-01-2000 MAR-31-2000 7,524,000 0 192,000 35,000 17,000 7,860,000 555,000 111,000 9,026,000 967,000 0 0 2,000 59,000 6,465,000 9,026,000 157,000 192,000 6,000 95,000 1,298,000 0 30,000 (1,168,000) 0 (1,168,000) 2,028,000 0 0 860,000 0.16 0.16