NATIONAL UNION FIRE INSURANCE COMPANY OF PITTSBURGH, PA., ALLIANZ GLOBAL RISKS US INSURANCE COMPANY, ACE AMERICAN INSURANCE COMPANY; ZURICH AMERICAN INSURANCE COMPANY, GREAT LAKES INSURANCE SE, XL INSURANCE AMERICA, INC., GENERAL SECURITY INDEMNITY COMPANY OF ARIZONA, ASPEN INSURANCE UK LTD, NAVIGATORS MANAGEMENT COMPANY, INC., IRONSHORE SPECIALTY INSURANCE COMPANY, VALIDUS SPECIALTY UNDERWRITING SERVICES, INC., and HDI-GERLING AMERICA INSURANCE COMPANY
v.
WESTLAKE CHEMICAL CORPORATION and AXIALL CORPORATION