Yahoo has been heavily criticised by consumer groups after an update to the terms and conditions of its webmail and messaging service appeared to give the company permission to snoop on the content of messages in order to sell advertising.
Which? Computing revealed that Section c. of Yahoo Mail's Additional Terms Of Service reads: "By using the Services, you consent to allow Yahoo's automated systems to scan and analyse all incoming and outgoing communications content sent and received from your account (such as Mail and Messenger content including instant messages and SMS messages)."
It goes on to say that Yahoo Mail users will not be able to opt-out of the feature, and that it is the responsibility of the individual to inform non-Yahoo contacts that the content of their messages could be read by a third party.
Georgina Nelson, a senior Which? in-house lawyer, advised any Yahoo users who object to the new terms of service to switch email providers.
"The obligation to notify those who email you that their message will be scanned is nonsensical and unrealistic. When exactly are you supposed to do this?" she said.
"This is another example of creeping behavioural advertising which, we believe, is a gross violation of internet users' privacy. Most consumers would be horrified to learn that their email can be read in order to open the door to targeted advertisers."
Daniel Hamilton, director of Big Brother Watch, argued that the changes give Yahoo the power to "analyse vast amounts of personal data".
"Web users have a right not to see their personal communications trawled through in order to boost Yahoo's advertising revenue," he added.
"Yahoo should abandon these changes before the crucial bond of trust between it and its users is damaged beyond repair."
Yahoo defended the updated terms by telling Which? that the service identifies only "words, links, people and subjects from their email" in order to provide "personally relevant product features and content" and to "match and serve targetted advertising", as well as spam and anti-malware functionality.
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