When President Obama first took office, much was made about his affinity for the BlackBerry and the ease of communicating via email and text. He didn't want to give it up, but federal agencies were concerned, both for his security and about retaining the communications for the National Archives.
There were debates and discussions on the issue, but eventually, the National Security Agency and others acquiesced. The president kept a secure smartphone, and procedures were set so that official communications were maintained for the archives. Since then, the White House has ventured into video addresses and Twitter posts as well, all with the caveat that official communications will be retained.
The National Archives and Records Administration played a major role in those decisions, so it's no surprise that the NARA got involved quickly after hearing rumors that the Securities and Exchange Commission destroyed files on thousands of preliminary investigations after they had been closed. According to nextgov, NARA said the SEC did not have authority to dispose of the files "because an NARA-approved disposition schedule did not exist."
Some of the Matters Under Inquiry files deleted, the story says, include Bernie Madoff, insider trading at Goldman Sachs and cases involving the SAC Capital hedge fund.