This year is likely to see a new fight over whether Verisign should be forced to create a “thick” Whois database for .com and its other generic top-level domains.

While Verisign has taken a deliberately ambivalent position on whether ICANN policy talks should kick off, the community is otherwise split on whether a mandatory thick Whois is a good idea.

Currently, only .com, .net, .name and .jobs – which are all managed on Verisign’s registry back-end – use a thin Whois model, in which domain name registrars store their customers’ data.

Other gTLDs all store registrant data centrally. Some “sponsored” gTLD registries have an even closer relationship with Whois data — ICM Registry for example verifies .xxx registrants’ identities.

But in a Preliminary Issue Report published in November, ICANN asked whether it should kick off a formal Policy Development Process that could make thick Whois a requirement in all gTLDs.

In comments filed with ICANN last week, Verisign said:

As the only existing registry services provider impacted by any future PDP on Thick Whois, Verisign will neither advocate for nor against the initiation of a PDP. … Verisign believes the current Whois model for .com, .net, .name and .jobs is effective and that the proper repository of registrant data is with registrars — the entities with direct connection to their customers. However, if the community, including our customers, determines through a PDP that “going thick” is now the best approach, we will respect and implement the policy decision.

Thick Whois services make it easier to find out who owns domain names. Currently, a Whois look-up for a .com domain can require multiple queries at different web sites.

While Whois aggregation services such as DomainTools can simplify searches today, they still face the risk of being blocked by dominant registrars.

The thin Whois model can also make domain transfers trickier, as we witnessed just last week when NameCheap ran into problems processing inbound transfers from Go Daddy.

ICANN’s Intellectual Property Constituency supports the transition to a thick Whois. It said in its comments:

Simplifying access to this information through thick Whois will help prevent abuses of intellectual property, and will protect the public in many ways, including by reducing the level of consumer confusion and consumer fraud in the Internet marketplace. Thick Whois enables quicker response and resolution when domain names are used for illegal, fraudulent or malicious purposes.

However, Verisign noted that a thicker Whois does not mean a more accurate Whois database – registrars will still be responsible for collecting and filing customer contact records.

There are also concerns that a thick Whois could have implications for registrant privacy. Wendy Seltzer of the Non-Commercial Users Constituency told ICANN:

Moving all data to the registry could facilitate invasion of privacy and decrease the jurisdictional control registrants have through their choice of registrar. Individual registrants in particular may be concerned that the aggregation of data in a thick WHOIS makes it more attractive to data miners and harder to confirm compliance with their local privacy laws.

This concern was echoed to an extent by Verisign, which noted that transitioning to a thick Whois would mean the transfer of large amounts of data between legal jurisdictions.

European registrars, for example, could face a problem under EU data protection laws if they transfer their customer data in bulk to US-based Verisign.

Verisign also noted that a transition to a thick Whois would dilute the longstanding notion that registrars “own” their customer relationships. It said in its comments:

As recently as the June 2011 ICANN meeting in Singapore, Verisign heard from several registrars that they are still not comfortable with Verisign holding their customers’ data. Other registrars have noted no concern with such a transition

ICANN staff will now incorporate these and other comments into its final Issue Report, which will then be sent to the GNSO Council to decide whether a PDP is required.

If the Council votes in favor of a PDP, it would be many months, if at all, before a policy binding on Verisign was created.

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