Britain's Parliament has just given the world an unprecedented look at the ruthless tactics of Facebook's executive team.

On Wednesday, the Digital, Culture, Media and Sport Committee published leaked emails from the Silicon Valley tech giant's leadership team that had been obtained by Six4Three, an app developer that's locked in a legal battle with Facebook after it blocked its bikini photo app.

There are hundreds of pages of documents and emails, mostly dating from between 2012 and 2015, that detail the way Facebook allowed third-party apps to access friend data through its platform.

They provide a unique window into how Facebook's senior leaders privately discussed strategy and competition at a period of intense growth for the company, which has since been bogged down by numerous scandals and flatlining user numbers in key markets.

From Facebook's attempts to kneecap "strategic competitors" to CEO Mark Zuckerberg writing that his company's interests don't always match up with what's best for the world, here are some of the key takeaways from the documents.

1. Facebook had a list of "strategic competitors" that it restricted access to.

Zuckerberg personally oversaw a list of "strategic" competitors to the social network, and decided whether to restrict them from accessing valuable user data.

One undated memo stated that companies considered to be "strategic competitors" to Facebook were even more restricted in what they could access.

It added that Mark Zuckerberg personally reviewed the list of competitors, and either he or another senior executive had to personally sign off any further access to data these companies might want.

On the eve of the publication of the documents, Facebook announced it was relaxing restrictions on competitors' apps in an apparent attempt to get ahead of the news.

In an unattributed statement published on its website, Facebook said:

"We built our developer platform years ago to pave the way for innovation in social apps and services. At that time we made the decision to restrict apps built on top of our platform that replicated our core functionality. "These kind of restrictions are common across the tech industry with different platforms having their own variant including YouTube, Twitter, Snap and Apple."

2. Zuckerberg personally approved Facebook's decision to cut off social network Vine's data.

One of the Facebook competitors Mark Zuckerberg played a personal role in stamping on was video social network Vine.

In an email dated January 24, 2013 (the day Vine launched on iOS) VP Justin Osofsky proposed shutting down the new app's access:

"Twitter launched Vine today which lets you shoot multiple short video segments to make one single, 6-second video. As part of their NUX, you can find friends via FB. "Unless anyone raises objections, we will shut down their friends API access today. We've prepared reactive PR, and I will let Jana know our decision."

Zuckerberg responded: "Yup, go for it."

3. Facebook tried to figure out how to grab users' call data without asking permission.

Ever-hungry for user data, Facebook in 2015 explored trying to access Android users' call logs and SMS history to use to feed into features like "People You May Know," while acknowledging the risk of user anger.

"This is a pretty high-risk thing to do from a PR perspective nut it appears that the growth eam will charge ahead and do it," Michael LeBeau wrote.

Yul Kwon also said Facebook was looking into ways to grab call log data without even asking users for permission:

"Based on [the Growth team's] initial testing, it seems this would allow us to upgrade users without subjecting them to an Android permissions dialog at all," they wrote.

Facebook's statement said:

"This specific feature allows people to opt in to giving Facebook access to their call and text messaging logs in Facebook Lite and Messenger on Android devices. We use this information to do things like make better suggestions for people to call in Messenger and rank contact lists in Messenger and Facebook Lite."

4. Certain key apps were white-listed and given greater access to user data even after a broader clampdown.

In 2015, Facebook made major changes to its app developer platform – but a chosen few partners were "whitelisted", meaning they got more access to data than regular developers using Facebook's platform.

These included Airbnb, Netflix, and Lyft.

5. Zuckerberg privately admitted that what's good for the world isn't necessarily what's good for Facebook.

In one of the emails, Zuckerberg candidly admits that Facebook's interests aren't always aligned with those of its users and the broader world.

Discussing third-party apps' access to Facebook's platform, the CEO talked about how to try to ensure users shared content on Facebook, rather than external platforms – even if it isn't in the users' best interests.

"However, that may be good for the world but it's not good for us unless people also share back to Facebook and that content increases the value of our network. So ultimately, I think the purpose of platform – even the read side is to increase sharing back into Facebook," he wrote.

6. Zuckerberg suggested users' data was worth 10 cents a year.

Facebook has insisted that it has never sold user data – but one of the revelations from the documents is that the company discussed the possibility of charging for access to it.

In one October 2012 email, Zuckerberg discussed a monetisation model that would let developers use Facebook's login tools or publish to Facebook for free, but would charge for "reading" data.

How much did he value his users at? Around 10 cents each, per year.

"A basic model could be: Login with Facebook is always free … Pushing content to Facebook is always free … Reading anything, including friends, costs a lot of money. Perhaps on the order of $US0.10/user each year," he wrote.

In its response, Facebook said:

"We explored multiple ways to build a sustainable business with developers who were building apps that were useful to people. "But instead of requiring developers to buy advertising – the option discussed in these cherrypicked emails – we ultimately settled on a model where developers did not need to purchase advertising to access APIs and we continued to provide the developer platform for free."

7. Execs discussed the single biggest threat to Facebook.

What does Facebook consider its single biggest threat?

According to an email written by exec Sam Lessin in 2012 addressed to Zuckerberg, it's not one rival site or app – it's lots of them.

"The number one threat to Facebook is not another scale social network, it is the fracturing of information / death by a thousand small vertical apps which are loosely integrated together," he wrote.

"This will either happen because there is fundamentally no 'return' on the centralization of information / the [social] graph OR it will happen because we sell off the graph piecemeal for less than it is worth and in the process destroy efficiency and value."

This article was originally published by Business Insider.

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