Standard & Poor’s put Oxy on its creditwatch list.

It was the second credit-rating firm to raise a red flag on Occidental Petroleum’s creditworthiness in the wake of a possible $800-million tax assessment in Colombia and a $724-million jury verdict against Occidental in Cheyenne, Wyo. After a $1.50-per-share plunge on Monday, the Los Angeles-based oil company’s stock Tuesday rose 12.5 cents a share. In a statement, the company said: “Neither case should have a material adverse effect upon the consolidated financial position of Occidental.”