WOT Services, Ltd is a Finnish company that runs the partly crowdsourced Internet website reputation rating tool Web of Trust (WOT). The installed WOT browser add-on shows its users the reputations of websites, which are calculated through a combination of user ratings and data from other sources. To generate revenue WOT licenses the use of its reputation database to other businesses.
WOT was founded in 2006 by Sami Tolvanen and Timo Ala-Kleemola, who wrote the WOT software as post-graduates at the Tampere University of Technology in Finland. They launched the service officially in 2007, with serial entrepreneur and angel investor Esa Suurio as CEO. In November 2009 Suurio moved on to his next endeavor.
The rating tool
The WOT browser add-on does two things: (1) it sends user ratings to the WOT site, and (2) it displays the computed results via color-coded icons in the user's browser tool-bar and next to external links on the pages of leading search engines, email services and social network sites. The add-on source code is public.
According to the company information their program software is designed to compute the measure of trust the rating users have in websites, enhanced with data from a number of third-party sources. The user rating system claims to be meritocratic; the weight of ratings are algorithmically calculated for each user individually.
The New York Times and the Washington Post made mention of WOT  and the add-on was mentioned and reviewed by the trade press and download sites. The reviewers opinions vary from good to excellent, though some critical remarks were made.
PC Magazine's Neil Rubenking concluded "Web of Trust's protection is free, and it doesn't impact browsing speed; it's well worth trying out". However, on the minus side he found several clearly adult sites unrated and he wished WOT would also rate sponsored search results, like its main competitors do. 
PC World's Preston Gralla concluded: "Try WOT (Web of Trust), an excellent--and free--browser add-on that offers protection", and Rick Broida wrote in an article "I also highly recommend Web of Trust, a free browser plug-in that shows you if Web links are safe--before you click them".
Softpedia reviewer Ionut Ilascu wrote: "The reliability of the service has grown in the past years, despite voices accusing it of being exactly the opposite of what it should be, and proof is the collaboration with Facebook, Opera and Mail.ru Group.", concluding "As a service, WOT (Web of Trust) may be viewed as biased, but the latest developments in balancing the user opinion in order to provide relevant information point to the contrary. The extension is non-obtrusive but still has room for improvements.".
In 2011 a lawsuit in Florida, USA against WOT and some its forum members, demanding to remove ratings and comments, was dismissed with prejudice. In Germany some preliminary injunctions were issued by courts, to delete feedback.
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- Widenius, Michael (16 February 2009). "Monty says - Life goes on and making the internet more secure with Web of Trust (WOT)". Retrieved 21 December 2014.
- "Facebook Security - Keeping You Safe from Scams and Spam". 12 May 2011. Retrieved 31 May 2014.
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- Rubenking, Neil J. (Aug 13, 2009). "PC Magazine - Web of Trust Review and Rating". Retrieved 17 May 2011.
- Gralla, Preston (26 April 2009). "PCWorld - Say WOT? Web of Trust Rates Web Site Safety". Retrieved 21 December 2014.
- Broida, Rick (4 January 2010). "PCWorld - Make Your New PC Hassle-Free, Part 3: Keep It Secure". Retrieved 21 December 2014.
- Murphy, David (2 December 2009). "Maximum PC - Firefox Add-on of the Week: Web of Trust". Retrieved 21 December 2014.
- Ilascu, Ionut (26 September 2013). "Softpedia - Web of Trust Review". Retrieved 21 December 2014.
- "FAQ: Web of Trust". The Nation. Retrieved 17 January 2015.
- "WOT Wins Lawsuit In The US". ArcticStartup. 13 December 2011. Retrieved 22 December 2011.