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Exhibit 21.1

SUBSIDIARIES OF REGISTRANT

Rambus Delaware LLC
Rambus Deutschland GmbH (Germany)
Rambus International Ltd.
Rambus K.K. (Japan)
Rambus Ltd. (Grand Cayman Islands, BWI)
Rambus Chip Technologies (India) Private Limited
Rambus Korea, Inc. (Korea)
Cryptography Research, Inc.
Unity Semiconductor Corporation

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Exhibit 21.1

SUBSIDIARIES OF REGISTRANT