The Burton Group have released the results of their research that concludes that Symantec (Vontu), RSA (Tablus) and Websense (Port Authority) are the leading DLP vendors.
Burton’s choice is indicative of the Americanization of the information security space, where government compliance regulation and large security vendor marketing agendas appear to drive US customer security decisions. (Note that compliance is not equivalent to security  for several fundamental reasons as I noted in my post Compliance is the new security standard)
Outside the US, the story is a bit different.
We hardly encounter RSA in EMEA as a DLP solution – RSA Security have the largest development group dedicated to data loss prevention and that counted for a lot in the Burton study. I’m not sure why. Great software today is usually written by small teams, I would not equate number of programmers with quality of software.
I recently met Bill Nagel from Forrester and he told me that in a seminar that Forrester ran recently (September 09) in Holland – none of the CISO’s at the seminar were planning a DLP implementation this year and only 20% were considering a DLP implementation in 2010.
Clients I speak with in EMEA are less interested in enterprise information protection (although the advantages are patently clear, the technology is patently not there yet…) and more interested in exploring tactical solutions like DLP “Lite” – monitoring SMTP and HTTP channels for data security violations and using that information to enforce business process and improve employee behavior.

Symantec and Websense were not surprises – but not for the reasons Burton mentioned – from my view in the trenches, Symantec and Websense have the strongest distribution channels and resellers.

The Burton Group analysis surveyed vendors on their market and product strategy and included interviews with the customers to gauge customer satisfaction. A live demonstration of each vendor product was also conducted using a scenario designed by the analysts. Once completed, the vendors were ranked based on vendor viability, customer satisfaction, market leadership, sales, service, support and product evaluation.

• Symantec Corp. for its success in leveraging its 2007 acquisition of DLP startup Vontu
• RSA, the security division of EMC, for its extensive capabilities and its close partnership with Microsoft, which adds digital rights management features. Burton Group’s analysis also said RSA had the largest development team in place
• Websense also made the list for consistently expanding its DLP capabilities since its 2007 acquisition of PortAuthority Technologies.

Verdasys was also named as a “conservative contender” for its strong capabilities and diversified industry footprint. Although its technology is only host-based, the vendor has partnered with Fidelis Inc., adding network-based DLP features. The Burton Group analysis also cited NextLabs for having a strong strategy, vision and features for identity-integrated DLP and for using Extensible Access Control Markup Language (XACML), a standards-based protocol that could help it develop extensive features.