Told that its indefinite retention of ad-click data was unacceptable, Facebook agreed to retain such data for no more than two years, and seems to be keeping it for less time. In a data dump downloaded on Aug. 10, the first referenced ad-click stored by Facebook is dated July 2, while in one downloaded on Sept. 10, the first mentioned ad-click is dated July 20. The earliest two ad-clicks from the first data dump don't appear in the second, suggesting Facebook is retaining the data for about two months. That, of course, assumes that Facebook provides its users with all their personal data -- and that is not always easy to believe.
In my downloaded data, for instance, part of my private message history is missing. Facebook's online history of my conversation with one of my friends dates back to July 9, 2011, with hundreds of messages shared, but the data dump only contained the messages shared on Sept. 1, 2012. Another conversation, started on Aug. 19, 2010, only appeared in the data dump as of July 6, 2011. Other, older messages were also missing.
Max Schrems, an Austrian law student who runs Europe vs. Facebook, a group pushing the company to respect privacy laws, doubts that Facebook sends users all the data it holds about them. He was among the first to ask Facebook to send him a copy of his personal data. A year ago, the company sent him a raw file of data consisting of a stack of papers and a CD that together contained far more information than is available for download today.
Pictures he had uploaded to Facebook, for instance, were accompanied by metadata such as the GPS location, the IP address used to upload the photo and the camera make and model, he said. But with Facebook's download tool today, he only gets the raw picture without the metadata.
"Then there are other things. For example: if you delete messages on Facebook they still hold them, and in the download tool you don't get the deleted messages," said Schrems, who added that the deleted messages did appear in his raw data file a year ago. Likewise, "If you delete friends, or if friends delete you, they'll still store it but you don't get the deleted friend information all the time," he said.
In addition, the information provided by Facebook is scattered across different places, which makes it hard to track if all the information is there, Schrems said.
Besides the two data downloads and the online activity log that Facebook highlights, other personal information can be found in the account settings, Schrems said. "A normal user is entitled to get everything from Facebook. Today, users have to hunt all over Facebook to get it."
Sign up for Computerworld eNewsletters.