(CNN) - Facebook is bad for democracy and its executives have put profits over their civic responsibilities, an early investor in the company charges in a new book.
Tech investor Roger McNamee makes these claims in "Zucked: Waking up to the Facebook catastrophe," due out on Tuesday.
McNamee has said he served as a mentor to CEO Mark Zuckerberg in Facebook's early years and discouraged the young entrepreneur from selling the business for $1 billion to a bigger tech company. Facebook is currently worth about $500 billion.
McNamee argues in the book that the business models of Facebook and other tech giants are bad for society due to their reliance on advertising. He says platforms need to keep people on their sites as long as possible and often the most polarizing, divisive, and emotive content is what keeps people engaged.
"Facebook and Google designed their products to create habits that for many people become an addiction," McNamee told CNN Business on Monday. "They manipulate attention for profit and enable bad actors to manipulate some users in ways that harm them and others."
But he argues the public has "more power than they realize."
"They can withdraw some of the attention internet platforms depend on by altering their usage and demand action by policy makers in government," he told CNN Business.
Facebook is pushing back. "We take criticism seriously," a Facebook spokesperson said in a statement provided to CNN Business. "Over the past two years, we've fundamentally changed how we operate to better protect the safety and security of people using Facebook. The reality is Roger McNamee hasn't been involved with Facebook for a decade."
McNamee has long been a vocal critic of Facebook. In an interview with CNN Business last spring, McNamee said he had become concerned about the potential dangers of Facebook in 2016 when he noticed ostensibly pro-Bernie Sanders pages sharing what he called "cruel" and "misogynistic" memes about Hillary Clinton. McNamee said he suspected the memes were not actually be from real Sanders supporters.
In October of that year, McNamee said, he reached out to Zuckerberg and COO Sheryl Sandberg to express his concerns about "bad actors" potentially exploiting Facebook.
Although the executives were cordial and arranged for him to talk to someone else on their teams, he said he didn't believe the company had taken his concerns seriously.
It later emerged that a Russian government-linked troll group had been active on Facebook throughout the 2016 election, posing as Americans on both sides of the political divide. It is not known if the pages McNamee had noticed were authentic or not.
While Facebook did not mention him by name, on Monday Facebook published a blog post headlined "What is Facebook doing to address the challenges it faces?" that addressed some of the issues McNamee raises in his book.
"Although we didn't do enough to anticipate some of these risks, we've now made fundamental changes," Facebook said in the blog post. "This past year we've invested record amounts in keeping people safe and strengthening our defenses against abuse. We've also provided people with far more control over their information and more transparency into our policies, operations and ads."
McNamee said the goal of the book is to "help everyone understand the platforms they love to use have a dark side and what they can do to protect themselves and their children."
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