The SEC alleges that unknown traders took risky bets that Onyx's stock price would increase by purchasing call options on June 26, 27 and 28, the three trading days before the announcement. Through quick, cross country coordination between the agency's Los Angeles and New York offices, the SEC took emergency action to freeze the traders' assets before courts closed for the holiday.

"This action demonstrates that the SEC will not hesitate to freeze the assets of suspicious foreign traders when the timing and size of their trades indicate that they were misusing inside information, and use of foreign accounts will not dissuade us," said Michele Wein Layne, Director of the SEC's Los Angeles Regional Office.

According to the SEC's complaint filed in federal court in Manhattan, on June 30, 2013 Onyx announced that it had received, but rejected, an unsolicited proposal from Amgen to acquire all of Onyx's outstanding shares and share equivalents for $120 per share in cash. The Announcement also stated that Onyx's board of directors rejected Amgen's proposal and that Onyx had authorized its financial advisors to contact potential acquirers who may have an interest in a transaction with Onyx. Amgen's $120 per share price offer represented a 38% premium to Onyx's closing share price on Friday June 28, 2013. The complaint further alleges that as a result of the announcement, Onyx's share price increased from a close of $86.82 on over 51% on Monday July 1 compared with the prior trading day's closing price, and that the trading volume of its stock increased by over 900% that day. The complaint alleges that the traders, as a result of these well-timed trades, collectively earned a profit of approximately $4.6 million in just three days.

The SEC alleges that certain unknown traders were in possession of material nonpublic information about the offer to acquire Onyx at a substantial premium over the stock price at the time they made thy purchased Onyx call options, many of which were out-of-the-money, in the three trading days before the announcement. According to the complaint, the timing and size of the trades were highly suspicious because they constituted large increases over the historical volume for those call options purchased.

The emergency court order obtained by the SEC freezes the traders' assets related to the Onyx call options transactions and prohibits the traders from destroying any evidence. The SEC's complaint charges the unknown traders with violating Section 10(b) of the Securities Exchange Act of 1934 and Exchange Act Rule 10b-5. In addition to the emergency relief, the Commission is seeking a final judgment ordering the traders to disgorge their ill-gotten gains with interest, pay financial penalties, and permanently bar them from future violations.

The SEC's expedited investigation, which is continuing has been conducted by Melissia Buckhalter-Honore and Spencer Bendell. The litigation will be led by John Bulgozdy and Sam Puathasnanon of the Los Angeles Office with the assistance of Alexander Vasilescu of the New York Office. The SEC appreciates the assistance of the Options Regulatory Surveillance Authority (ORSA).