BT's chief security technology officer has accused the chief executives of big name tech companies such as Google and Facebook of "deliberately killing privacy" in their quest to boost profits.
Bruce Schneier branded Facebook the "worst offender", alleging that the site deliberately eroded privacy in order to successfully pursue its business model.
"We're not Facebook customers, we're Facebook's product it sells to its customers [the advertisers]," he said. "Facebook wants more users because it's in the business of advertising."
The social networking firm came in for a torrid time in Schneier's keynote speech and subsequent press conference at RSA Conference Europe 2010.
The security expert argued that Facebook talks big on privacy but actually does little to protect it, for example making privacy policies hard to find and limiting user choice within them.
Facebook rolled out enhancements to its service last week designed to give users greater control over their profiles and how they interact with others on the site, but Schneier argued that it is unlikely fundamentally to improve user privacy.
"Facebook is trying to fix this but I'm not convinced it's going to work, although it is a step in the right direction," he added.
Schneier maintained that ISPs are technologically in a "good place" to theoretically impose controls which would help protect privacy on such sites, although he believes that the only way this would come about is through legislation.
"I'd like to see governments pass broad privacy protection laws," he said. " These are not technology problems, they're social problems and they need to be solved at a higher level."
A Facebook spokesperson argued in response that "nothing is more important to Facebook than the safety of its users".
Facebook also directed V3.co.uk to a July blog post by the firm's chief operating officer, Sheryl Sandberg, which promised that Facebook provides "relevant and interesting advertising content to you in a way that protects your privacy completely".
"We never share your personal information with advertisers. We never sell your personal information to anyone," Sandberg wrote at the time.
"These protections are yours no matter what privacy settings you use; they apply equally to people who share openly with everyone and to people who share with only select friends."
Facebook also introduced simpler privacy controls in May which were communicated to all users, and has an online Help Centre, Safety Centre and Guide to Privacy designed to help answer any questions users may have, the firm added.
HomePod delay means Apple will miss Christmas sales
Reports of Toshiba PC sale plans come after it sold its TV manufacturing unit to Hisense
IoT Accelerator programme intended to stimulate tech investment in Wales
Vote follows claims of Russian interference, even though Clinton out-spent Trump 2-to-1