Lengthy post from Graywolf in answer to the question “Does Google use whois information“?

The short answer?

Probably. Just a little.

The long answer? Follow the link above.

In summary, Google possibly use whois data for:

• a site under a manual review
• checking on domains that are close to expiring
• cross-matching whois data
• corresponding phone number and physical address

Only Google know for sure, but good article.