Occidental Petroleum Corp. said that it liquidated its remaining stake in Houston-based oil company Lyondell Chemical Co.

The Los Angeles-based oil company said in a filing with the security and Exchange Commission that it sold 14 million Lyondell shares on the open market. The sale should generate about $538 million, based on Lyondell closing price Wednesday of $38.48.

Shares in Occidental were up $1.72, or 3 percent, to $61.43 in afternoon trading Thursday on the New York Stock Exchange.