0001104659-23-123615 Sample Contracts

GOLUB CAPITAL BDC, INC. $450,000,000 Aggregate Principal Amount of 7.050% Notes due 2028 UNDERWRITING AGREEMENT Dated: November 30, 2023 GOLUB CAPITAL BDC, INC. $450,000,000 Aggregate Principal Amount of 7.050% Notes due 2028 UNDERWRITING AGREEMENT

Underwriting Agreement • December 5th, 2023 • GOLUB CAPITAL BDC, Inc. • New York

• Contract Type
  Underwriting Agreement
• Filed
  December 5th, 2023
• Company
  GOLUB CAPITAL BDC, Inc.
• Jurisdiction
  New York

FOURTH SUPPLEMENTAL INDENTURE between GOLUB CAPITAL BDC, INC. and as Trustee Dated as of December 5, 2023 FOURTH SUPPLEMENTAL INDENTURE

Fourth Supplemental Indenture • December 5th, 2023 • GOLUB CAPITAL BDC, Inc.

• Contract Type
  Fourth Supplemental Indenture
• Filed
  December 5th, 2023
• Company
  GOLUB CAPITAL BDC, Inc.

THIS FOURTH SUPPLEMENTAL INDENTURE (this “Fourth Supplemental Indenture”), dated as of December 5, 2023, is between Golub Capital BDC, Inc., a Delaware corporation (the “Company”), and U.S. Bank Trust Company, National Association (as successor in interest to U.S. Bank National Association), as trustee (the “Trustee”). All capitalized terms used but not otherwise defined herein shall have the meaning set forth in the Base Indenture (as defined below).