(Adds details on pharmaceutical company stake)
MEXICO CITY, Feb 17 (Reuters) - Mexican billionaire Carlos Slim and his family reduced their exposure to Argentine energy company YPF last year, selling just over 10 million shares, according to a filing with the U.S. Securities and Exchange Commission on Tuesday.
The businessman, his family and their companies now directly and indirectly hold 22,070,000 YPF shares, equivalent to a 5.6 percent stake, down from 8.2 percent in their last filing a year earlier.
Slim and his family hold the YPF shares through their holding company Inmobiliaria Carso and their bank, Grupo Financiero Inbursa, the filing showed.
A separate filing showed that Slim and his family, through Inmobiliaria, last year purchased 1,335,202 shares for a stake of 6.6 percent in a U.S. pharmaceutical company called Atara Biotherapeutics.
Atara, which focuses on muscle-wasting conditions and oncology, went public in October.
Reporting by Elinor Comlay; editing by Matthew Lewis