http://whois.net has been crawled 989 times going all the way back to January 19, 1998.

A crawl can be a duplicate of the last one. It happens about 25% of the time across 420,000,000 websites. FAQ
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January 7, 2011

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January 10, 2011

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January 29, 2011

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February 7, 2011

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February 8, 2011

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February 18, 2011

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February 19, 2011

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February 23, 2011

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March 5, 2011

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March 13, 2011

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March 25, 2011

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April 9, 2011

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April 22, 2011

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April 30, 2011

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May
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May 9, 2011

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May 18, 2011

1 snapshot

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May 19, 2011

1 snapshot

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May 31, 2011

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Jun
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Jul
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July 23, 2011

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July 24, 2011

2 snapshots

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Aug
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Sep
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Oct
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Nov
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Dec
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Note

This calendar view maps the number of times http://whois.net was crawled by the Wayback Machine, not how many times the site was actually updated. More info in the FAQ.