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EX-31.2 - EX-31.2 - MERRIMACK PHARMACEUTICALS INCa2208526zex-31_2.htm
EX-31.1 - EX-31.1 - MERRIMACK PHARMACEUTICALS INCa2208526zex-31_1.htm
EX-32.1 - EX-32.1 - MERRIMACK PHARMACEUTICALS INCa2208526zex-32_1.htm
EX-32.2 - EX-32.2 - MERRIMACK PHARMACEUTICALS INCa2208526zex-32_2.htm
10-K - 10-K - MERRIMACK PHARMACEUTICALS INCa2208526z10-k.htm

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Exhibit 21.1

SUBSIDIARIES OF THE REGISTRANT

Name
  Jurisdiction of Incorporation
Merrimack Pharmaceuticals (Bermuda) Ltd.*   Bermuda
Merrimack Pharmaceuticals UK Limited*   UK
Silver Creek Pharmaceuticals, Inc.    Delaware

*
wholly owned



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SUBSIDIARIES OF THE REGISTRANT