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|Type of business||Public|
|Type of site||Professional network service|
|Available in||English, French, German, Italian, Portuguese, Spanish, Russian|
|Founder(s)||Dan Serfaty, Thierry Lunati|
|Revenue||$40 million (2009 estimation)|
|Slogan(s)||Your network is more powerful than you think!|
|Alexa rank||672 (April 2014[update])|
Viadeo was founded under its original name, Viaduc, in May 2004 by Dan Serfaty, a graduate of the HEC School of Management in Paris, and Thierry Lunati, a graduate of École centrale Paris. The name was changed to Viadeo in November 2006.
From November 2006 to August 2007, Viadeo raised €5 million twice in funding from investors AGF Private Equity and Ventech. Later that year, Viadeo announced the acquisition of Tianji.com, a Chinese business social network.
Six months after purchasing Tianji, in July 2008 Viadeo acquired its Spanish competitor ICTnet. Launched in 1995, ICTnet had 300,000 members and is popular in South America.
In early 2009, Viadeo acquired the Indian professional social networks services, ApnaCircle. ApnaCircle, with 300,000 members at the time of the acquisition, was founded by Yogesh Bansal and later joined by Sabeer Bhatia, co-founder of Hotmail, as board member.
On 13 October 2009, Viadeo announced the acquisition of the Canadian contact management website, unyk.com. At the time, unyk had 16 million members around the world, and this made Viadeo second only to its main competitor LinkedIn in terms of total membership.
The company is headquartered in Paris, and employs a global staff of 450, with offices in London, Madrid, Barcelona, Milan, Beijing, New Delhi, Mexico City, Montreal and San Francisco. In 2009, Viadeo had estimated annual turnover of $40 million  and is profitable since last quarter of 2009.
In August of 2015, Viadeo announced they had engaged in an advertising campaign in France to promote a 'new vision' and that the member base had passed the 10 million mark in France.
- Google OpenSocial: Viadeo is partner since launch in 2007
- IBM Lotus Notes: Viadeo available for professionals using IBM Lotus Notes
- Microsoft Outlook Connector: Viadeo available on Outlook.
- "Ferris Research - Viadeo: Professional Networking". Ferris Research. 16 December 2009. Retrieved 10 July 2010.
- "Viadeo.com Site Info". Alexa Internet. Retrieved 2014-04-01.
- "Viadeo Raises $32M To Expand Its Professional Social Network In China, Russia And Beyond". TechCrunch.com. 11 April 2012. Retrieved 17 July 2012.
- "Viadeo continues to grow: 65 million members worldwide, including 25 million in China". Viadeo SA. 11 December 2014. Retrieved 24 February 2015.
- "Réseaux sociaux: Viaduc devient Viadeo pour attaquer l'international," ZDnet.fr, 27 Nov. 2006
- "LinkedIn Competitor Viadeo Raises €5 Million". mashable.com. 31 August 2007. Retrieved 10 July 2010.
- "Viadeo acquiert le réseau social professionnel espagnol ICTnet" (in French). TechCrunch.com. 12 July 2008. Retrieved 10 July 2010.
- "French Business Networking Site Viadeo Acquires ApnaCircle". VC Circle. 14 February 2009. Retrieved 10 July 2010.
- "Viadeo buys Unyk, second only to LinkedIn". Reuters. 13 October 2009. Retrieved 13 July 2010.
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- "Viadeo opens Asia/Pacific headquarters in San Francisco" (PDF). Viadeo. 19 May 2010. Retrieved 10 July 2010.
- "Viadeo: Results for the First Half of 2015". Retrieved 2015-09-11.
- "Checkmate? MySpace, Bebo and SixApart To Join Google OpenSocial (confirmed)". TechCrunch.com. 1 November 2007. Retrieved 16 July 2010.
MySpace and Six Apart join Orkut, Salesforce, LinkedIn, Ning, Hi5, Plaxo, Friendster, Viadeo and Oracle as announced Google partners.
- "Viadeo's "Global-Yet-Local" B2B Social Network Integrates with IBM Lotus Software to Provide Collaboration Tools for Professionals". IBM. 18 January 2010. Retrieved 16 July 2010.
- "Viadeo signs a partnership agreement with Microsoft as Office 2010 is launched worldwide" (PDF). Viadeo. 13 May 2010. Retrieved 16 July 2010.