A copy of'The Observer' shows an advertisement paid by Facebook in London, March 25, 2018. Facebook Chief Executive Mark Zuckerberg apologized for a "breach of trust" involving misused data from millions of Facebook users. The ads also appeared in The New York Times, Washington Post and Wall Street Journal. SAN FRANCISCO -- As Facebook continues to buffet winds of criticism, its founder took out full page ads in U.S. and British newspapers Sunday to apologize to consumers for not properly securing their personal data. "This was a breach of trust, and I'm sorry we didn't do more at the time," Mark Zuckerberg said in the signed ad, which was published in The New York Times, The Wall Street Journal, The Washington Post and six British papers.