ACHN 2018 Proxy Statement

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT As of February 28, 2018, or such date as indicated below, the table below indicates the shares of our common stock beneficially owned by (1) each of our directors, (2) our principal executive officer, our principal financial officer, our two other most highly compensated executive officers who were serving as executive officers on December 31, 2017, and two additional individuals who would have been among our three most highly compensated executive officers, but for the fact that they were not serving as executive officers on December 31, 2017, whom we refer to collectively as our “named executive officers,” (3) all of our current directors and executive officers as a group and (4) all persons known by us to beneficially own more than 5% of our outstanding common stock. Beneficial ownership is determined in accordance with rules of the SEC and includes shares over which the indicated beneficial owner exercises voting or investment power. Percentage of common stock outstanding is based on 137,959,277 shares of our common stock outstanding as of February 28, 2018. Shares of common stock subject to stock options and warrants that are currently exercisable, or exercisable within 60 days of February 28, 2018, are deemed outstanding for the purpose of computing the percentage ownership of the person holding such securities but are not deemed outstanding for computing the percentage ownership of any other person. Except as otherwise indicated in the footnotes to this table and subject to community property laws where applicable, we believe that each stockholder identified in the table has sole voting and investment power with respect to all shares listed opposite their names. 6