Eike Batista’s fortune continues to shrink. The Brazilian tycoon, worth an estimated $10.6 billion on Forbes 2013 Billionaires list (which used Feb. 14 stock prices) has seen his fortune drop more than $1 billion in a little over a month. Batista controls a troubled empire of commodities and energy businesses through EBX Group, which is comprised of five companies listed on BM&FBovespa's Novo Mercado - the segment of Brazil's stock exchange with the highest standards of corporate governance - whose business is oil (OGX), energy (MPX), logistics (LLX), mining (MMX), offshore oil & gas services (OSX), and many others. His estimated net worth has fallen to just under $9.5 billion, down from $30 billion on February 2012 when he was the world’s seventh richest person. The slump began when OGX reported weak production figures for its first oil wells in June 2012.