Facebook users will see fewer posts from businesses and brands in the future after the company announced the biggest overhaul to its News Feed for years.
Messages and photos share by friends and families will take priority instead, the social media company announced on Thursday.
The move is an attempt to make users more engaged with the site by having “more meaningful social interactions”.
However, it raises serious questions for companies that have invested heavily in using Facebook pages to drive traffic to their websites.
Mark Zuckerberg, the Facebook co-founder, announced the “major change” in a post on the website on Thursday evening.
He appeared to admit that people who “passively” read Facebook posts and videos from businesses were left feeling less happy than when reading content from friends.
Mr Zuckerberg said he expected people to spend less time on Facebook as a result of the changes - a frank admission from a business leader - but predicted it would boost the company in the long term.
The changes fell short of a more radical move to split Facebook’s News Feed in two, which had been expected by some in the industry.
That innovation, tested in some countries in recent months, would have left commercial posts sitting on a completely separate feed from the main one.
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Mr Zuckerberg outlined a less absolute change in his post that will see commercial content deprioritised rather than removed from the News Feed all together.
“I'm changing the goal I give our product teams from focusing on helping you find relevant content to helping you have more meaningful social interactions,” he wrote.
“We started making changes in this direction last year, but it will take months for this new focus to make its way through all our products.
“The first changes you'll see will be in News Feed, where you can expect to see more from your friends, family and groups.
“As we roll this out, you'll see less public content like posts from businesses, brands, and media.
“And the public content you see more will be held to the same standard -- it should encourage meaningful interactions between people.”
The shake-up comes as Facebook, which now has more than two billion users, battles critics who have accused it of allowing fake news and Russian propaganda to circulate.
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The US election in 2016 saw a string of adverts making misleading or factually inaccurate statements about political candidates gain traction on the site.
The company has since admitted that as many as 126 million people - one-third of the US population - may have seen material posted by Russian-linked groups between 2015 and 2017.
Mr Zuckerberg initially dismissed criticism of how the site was used in the aftermath of Donald Trump's victory but has since pledged to make changes.
There have also been complaints that the News Feed - a stream of messages, photographs and videos - increasingly features posts from companies rather than friends.
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In his message, Mr Zuckerberg cites research about how users feel more happy when viewing content from people they know to justify the changes.
“We feel a responsibility to make sure our services aren’t just fun to use, but also good for people's well-being,” he wrote.
“So we've studied this trend carefully by looking at the academic research and doing our own research with leading experts at universities.
“The research shows that when we use social media to connect with people we care about, it can be good for our well-being.
"We can feel more connected and less lonely, and that correlates with long term measures of happiness and health.
“On the other hand, passively reading articles or watching videos - even if they're entertaining or informative - may not be as good.”
Mr Zuckerberg also warns the changes could hit traffic: “Now, I want to be clear: by making these changes, I expect the time people spend on Facebook and some measures of engagement will go down.
“But I also expect the time you do spend on Facebook will be more valuable. And if we do the right thing, I believe that will be good for our community and our business over the long term too.”
It is unclear exactly how Facebook will deprioritise posts that are made by companies, but it appears a more radical change will not be adopted for now.
A trial that split the Facebook News Feed in two - one for friends and family messages, another for those from companies and brands - has been running in six countries including Slovakia, Serbia and Sri Lanka.
However it triggered complaints that media companies saw traffic to their sites via Facebook drop by as much as 80 per cent.
If adopted worldwide, such a move could have had a major impact on news websites like Buzzfeed and Huffington Post which have focused on getting clicks through Facebook.
Speaking to The New York Times, Mr Zuckerberg said recently becoming a father had convinced him to change the website to focus on more "meaningful" social interactions.
“It’s important to me that when Max and August [his two daughters] grow up that they feel like what their father built was good for the world,” Mr. Zuckerberg said.