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Exhibit 21.1

Subsidiaries of Tucows Inc., a Pennsylvania corporation

1.

Tucows (Delaware) Inc., a Delaware corporation, is a wholly owned subsidiary of Tucows.

2.

Tucows.com Co., a Nova Scotia corporation, is a wholly owned subsidiary of Tucows (Delaware) Inc.

3.

Tucows Corp., a Mississippi corporation, is a wholly owned subsidiary of Tucows (Delaware) Inc.

4.

Tucows (UK) Limited, a company incorporated in England and Wales, is a wholly owned subsidiary of Tucows.com Co.

5.

Infonautics Corp., a Pennsylvania corporation, is a wholly owned subsidiary of Tucows.

6.

Tucows (Australia) Pty Limited.

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Exhibit 21.1

Subsidiaries of Tucows Inc., a Pennsylvania corporation