Exhibit Designation Nature of Exhibit Previously Filed as Exhibit to: 4(a) Indenture (for unsecured debt securities), dated as of November 1, 2000, between PSO and The Bank of New York, as Trustee. Registration Statement No. 333-100623, Ex 4( a )( b ) Registration Statement No. 333-114665, Ex 4( b )( c ) Registration Statement No. 333-133548, Ex 4( b )( c ) Registration Statement No. 333-156319, Ex 4( b )( c ) 4(b) Eighth Supplemental Indenture, dated as of November 13, 2009 between PSO and The Bank of New York Mellon, as Trustee, establishing terms of the 5.15% Senior Notes, Series H, due 2019. Form 8-K, Ex 4(a), dated November 13, 2009 4(c) Ninth Supplemental Indenture, dated as of January 19, 2011 between PSO and The Bank of New York Mellon Trust Company, N.A., as Trustee, establishing terms of 4.40% Senior Notes, Series I, due 2021. Form 8-K, Ex 4(a) dated January 20, 2011 *13 Copy of those portions of the PSO 2018 Annual Report (for the fiscal year ended December 31, 2018) which are incorporated by reference in this filing. *24 Power of Attorney. *31(a) Certification of Chief Executive Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. *31(b) Certification of Chief Financial Officer Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. *32(a) Certification of Chief Executive Officer Pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code. *32(b) Certification of Chief Financial Officer Pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code. 101.INS  XBRL Instance Document. 101.SCH  XBRL Taxonomy Extension Schema. 101.CAL  XBRL Taxonomy Extension Calculation Linkbase. 101.DEF  XBRL Taxonomy Extension Definition Linkbase. 101.LAB  XBRL Taxonomy Extension Label Linkbase. 101.PRE  XBRL Taxonomy Extension Presentation Linkbase. SWEPCo‡ File No. 1-3146 3(a) Composite of Amended Restated Certificate of Incorporation of SWEPCo. 2008 Form 10-K, Ex 3(a) 3(b) Composite By-Laws of SWEPCo amended as of February 26, 2008. 2007 Form 10-K, Ex 3(b) 4(a) Indenture (for unsecured debt securities), dated as of February 4, 2000, between SWEPCo and The Bank of New York, as Trustee. Registration Statement No. 333-96213 Registration Statement No. 333-87834, Ex 4( a )( b ) Registration Statement No. 333-100632, Ex 4(b) Registration Statement No. 333-108045, Ex 4(b) Registration Statement No. 333-145669, Ex 4( c )( d ) Registration Statement No. 333-161539, Ex 4( b )( c ) Registration Statement No. 333-194991, Ex 4( b )( c ) Registration Statement No. 333-208535, Ex 4( b )( c ) Registration Statement No. 333-226856, Ex 4( b )( c ) E-9