Spotify and Netflix both got access to Facebook users' private messages as part of features that allowed people to suggest movies, TV shows and music to their friends. For example, after watching a Netflix show, viewers were prompted to connect to Facebook to recommend it to others.

Netflix promoted this arrangement back in 2014 as a more private version of sharing, since the company claimed that Messenger allowed people to “easily, and privately, recommend the shows you love to the people you care about.” For this to happen, the Netflix app needed to be able to send Facebook messages. However, it was given the ability to also read, write and delete them, and to see all participants on a thread. Both Netflix and Spotify claimed to be unaware of such access, but documents show that Netflix still had access to users’ messages in 2017.

In 2011, when Yahoo and Facebook announced their partnership, Yahoo said that it was “putting people’s friends front and center to usher in an innovative way of connecting around content socially.” The company claimed that those who opted into its latest features would see their Facebook friends and the articles those friends had read, in a “facebar” at the top of the Yahoo News website.

This feature did not work very well and was soon abandoned. However, Yahoo continued to maintain special data access to the data of over 80,000 accounts, according to internal Facebook documents which were reviewed by The Times. As recently as summer 2018, Yahoo was still able to view a stream of posts from these people’s friends, and it is highly unclear what they did with all of this information. A spokesman for the company claimed that they did not use such information for advertising purposes.

Internal reports show that a Facebook feature dubbed “People You May Know,” a friend-suggestion tool, has long confused and unsettled Facebook users. Reports show that this tool has actually ended up recommending connections between patients of the same psychiatrist, people who had simply been in the same location, and even estranged family members. This has prompted suspicions that Facebook was closely tracking users’ movements and eavesdropping on their conversations, among other things.

According to reports, Facebook actually made deals with other companies in exchange for people’s contact details. Facebook then went on to use this data to create further friend network models and suggest even more connections. The partners that fed information to Facebook included Amazon, Yahoo, and Huawei.

Facebook also shared data with other websites in a program called “instant personalization.” These partners, including Bing and Rotten Tomatoes, were given access to users’ names, profile photos, gender and any other information they had made public.

Starting in 2010, people who visited one of the partner sites while logged into Facebook would have seen a blue bar on the screen which may have shown them what films their friends liked to watch, or given them tailored search results based on their Facebook preferences. Facebook eventually wound down this feature but it continued to allow certain websites access to much of the same data they had been receiving before.