CUSIP NO 450732-10-2 13G PAGE 3 OF 4 PAGES
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EXHIBIT 1
AGREEMENT
Pursuant to Rule 13d-1 (f) (1) under the Securities and Exchange Act of 1934,
the undersigned hereby agree that only one statement containing the information
required by Schedule 13G need be filed with respects to the ownership by each
of the undersigned of shares of iBasis, Inc.
This Agreement may be executed in any number of counterparts, each of which
shall be deemed an original.
Executed this 12th day of February, 2001
Dated: February 12, 2001
Xxxxxxx River Partnership VIII Limited Partnership
By: Xxxxxxx River VIII GP Limited Partnership
By: /s/ Xxxxxxx X. Xxxxxx, Xx.
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Xxxxxxx X. Xxxxxx, Xx.
Authorized General Partner
Xxxxxxx River VIII GP Limited Partnership
By: /s/ Xxxxxxx X. Xxxxxx, Xx.
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Xxxxxxx X. Xxxxxx, Xx.
Authorized General Partner
/s/ Xxxxxxx X. Xxxxxx, Xx.
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Xxxxxxx X. Xxxxxx, Xx.
/s/ Xxx X. Xxxxxxxxxxx
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Xxx X. Xxxxxxxxxxx
/s/ Xxxxxxx X. Xxx
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Xxxxxxx X. Xxx
