1. International Business Machines Corporation (16 from 164,108 patents)

2. Quickturn Design Systems, Inc. (8 from 84 patents)

3. Cadence Design Systems, Inc. (7 from 2,542 patents)

4. Other (1 from 832,680 patents)

5. Quicktum Design Systems, Inc. (1 from 1 patent)

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2. 8296121 - Method and apparatus for controlling power in an emulation system

3. 8160862 - Method and apparatus for controlling power in an emulation system

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6. 7827023 - Method and apparatus for increasing the efficiency of an emulation engine

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8. 7725304 - Method and apparatus for coupling data between discrete processor based emulation integrated chips

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10. 7107203 - High speed software driven emulator comprised of a plurality of emulation processors with improved board-to-board interconnection cable length identification system

11. 7089538 - High speed software driven emulator comprised of a plurality of emulation processors with a method to allow memory read/writes without interrupting the emulation

12. 7047179 - Clustered processors in an emulation engine

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14. 6901359 - High speed software driven emulator comprised of a plurality of emulation processors with a method to allow high speed bulk read/write operation synchronous DRAM while refreshing the memory

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