Brazil’s federal prosecutor’s office will seek to freeze some $650 million of mining magnate Eike Batista’s assets for alleged insider dealing, the prosecutor’s office said. According to the allegations, Mr. Batista defrauded investors by simulating a put option in Oct. 2012 that would have required him to invest at least $400 million in the oil and gas company OGX under his control.  The money ,however, was not invested, and the company ended up seeking bankruptcy protection in 2013 following the revelation that some of its major offshore oil areas were not viable. In reaction to the prosecutors’ complaint, Mr. Batista’s attorneys alleged that the company’s previous technical analyses had shown that the areas were viable and that the investment was cancelled only after subsequent analyses showed the contrary. Also as part of the complaint, prosecutors will seek to block assets of Mr. Batista’s sons Thor and Olin, and wife Flavia Sampaio, to whom Mr. Batista allegedly transferred funds. Mr. Batista was the founder and president of the EBX group of Brazilian energy and mining companies, and before OGX’s demise was listed among the world’s wealthiest individuals, with assets previously estimated near $34 billion.