How to Establish that Multiple Domain Names are Under Common Control

In UDRP proceedings, proving that disputed domain names share a common controlling person or entity is essential for complaint consolidation and demonstrating patterns of bad faith registration. While some respondents may attempt to obscure connections between domains, several reliable methods exist to establish common control.

Key methods of proving common control include:

1. WHOIS Evidence

• Historical WHOIS records showing matching registrant details, email addresses, or technical contacts
• Consistent patterns in privacy service usage across multiple domains
• Identical privacy service providers or proxy patterns suggesting coordinated registration

2. Technical Infrastructure Connections

• Domains pointing to the same IP addresses or IP address ranges
• Shared nameserver configurations across multiple domains
• Identical SSL certificates or certificate authorities
• Matching DNS record patterns, particularly MX and TXT records

3. Website Content and Structure

• Identical or highly similar HTML code bases across domains
• Matching error pages or server configuration patterns
• Shared analytics identifiers or tracking codes
• Consistent design elements, favicons, or metadata structures

4. Email Communication Patterns

• Correspondence from the same email addresses about different domains
• Consistent IP addresses or mail server configurations in email headers
• Domain registration confirmations sent to identical email addresses
• Similar email signature patterns or communication styles

5. Registration and Usage Behaviors

• Domains registered within close temporal proximity
• Consistent naming patterns or registration strategies
• Similar approaches to domain monetization
• Identical parking page providers or content delivery networks

6. Documentation Best Practices

• Preserve screenshots of all relevant web pages
• Maintain detailed technical logs with timestamps
• Archive historical WHOIS data before it expires
• Document all communication trails systematically

For UDRP panelists, the combined weight of multiple evidence types may prove more compelling than any single factor. Building a strong case requires careful documentation of various evidence forms that collectively demonstrate common control of the disputed domains.