by exploiting their friendship connection to the users who sold their data via the app. Following the revelations of the breach, several public figures, including industrialist Elon Musk and WhatsApp cofounder Brian Acton, announced that they were deleting their Facebook accounts, using the hashtag "#deletefacebook". Facebook was also criticized for allowing the 2012 Barack Obama presidential campaign to analyze and target select users by providing the campaign with friendship connections of users who signed up for an application. However, users signing up for the application were aware that their data, but not the data of their friends, was going to a political party. Unpublished photo disclosure bug In September 2018, a software bug meant that photos that had been uploaded to Facebook accounts, but that had not been "published" (and which therefore should have remained private between the user and Facebook), were exposed to app developers. Approximately 6.8 million users and 1500 third-party apps were affected. Unencrypted password storage In March 2019, Facebook admitted that it had mistakenly stored "hundreds of millions" of passwords of Facebook and Instagram users in plaintext (as opposed to being hashed and salted) on multiple internal systems accessible only to Facebook engineers, dating as far back as 2012. Facebook stated that affected users would be notified, but that there was no evidence that this data had been abused or leaked. In April 2019, Facebook admitted that its subsidiary Instagram also stored millions of unencrypted passwords. Facebook has denied for years that it listens to conversations and in turn releases ads based on them, however Facebook has been shown to have lied about their policies in the past. In 2016, Facebook stated "Facebook does not use your phone's microphone to inform ads or to change what you see in News Feed." a spokeswoman said, "some recent articles have suggested that we must be listening to people's conversations in order to show them relevant ads. This is not true. We show ads based on people's interests and other profile information, not what you’re talking out loud about." Investigations Cooperation with government requests Government and local authorities rely on Facebook and other social networks to investigate crimes and obtain evidence to help establish a crime, provide location information, establish motives, prove and disprove alibis, and reveal communications. Federal, state, and local investigations have not been restricted to profiles that are publicly available or willingly provided to the government;