Plaxo

Plaxo is an online address book and social networking service founded by Sean Parker, Minh Nguyen, and two Stanford engineering students, Todd Masonis and Cameron Ring. Plaxo, based in Sunnyvale, California, is a subsidiary of cable television company Comcast.

The company launched on Nov. 12, 2002, and was funded by venture capital including funds from Sequoia Capital. Plaxo announced May 14, 2008, that it had signed an agreement to be acquired by Comcast.Plaxo did not disclose the terms of the deal. Comcast completed its purchase of Plaxo on July 1, 2008. 

Plaxo provides automatic updating of contact information. Users and their contacts store their information on Plaxo's servers. When this information is edited by the user, the changes appear in the address books of all those who listed the account changer in their own books. Once contacts are stored in the central location, it is possible to list connections between contacts and access the address book from anywhere.

In May 2008, the website reported 20 million users.

A Plaxo plug-in supports major address books including Outlook/Outlook Express, Mozilla Thunderbird, and Mac OS X's Address Book, though other ones can be supported through an application programming interface. Additionally, Plaxo can also be maintained through an online version.

In March 2010, it was announced that CEO Ben Golub would be replaced by the company’s general manager, Justin Miller.

Partnerships

On July 7, 2005, Plaxo announced it had struck a deal with America Online to integrate its contact management service with its AOL and AOL Instant Messenger products.

Comcast

On May 7, 2007, Comcast announced that it had partnered with Plaxo in the launch of its universal communications service, SmartZone.

Plaxo 3.0

On June 24, 2007 Plaxo announced the public beta of a major new version of its service, called Plaxo 3.0. The service emphasizes "automated, multi-way sync.

Plaxo Pulse

On August 4, 2007 Plaxo announced the public beta of a social networking service called Plaxo Pulse. The service enables sharing of content from multiple different sources across the social web, including blogs, photos, social networking services, rating services, and others. Users can selectively share and view content according to either pre-determined categories (e.g. friends, family, business network) or customized groups. Plaxo Pulse was the first site to feature a working version of an OpenSocial container.

Charging for Outlook synchronization service

On July 30, 2009, the previously-free synchronization services for Outlook moved to Plaxo's premium (paid) service. According to Plaxo, "this change will allow us to continue to invest in the development and support of this valuable (but high-cost) feature". Existing users of the free service were offered a 20% lifetime discount on Plaxo premium.

Criticism

Plaxo received criticism from technology journalist David Coursey, who was upset about receiving a number of requests from Plaxo users to update their contact information (similar to spam email), and who wondered how the company was planning to make money from a free service that collects personal contact and network information. However after "changes at Plaxo and discussions with the company's remaining co-founders", Coursey reversed his stance. Plaxo also responded to these issues in a section of their website.