The following information is incorporated by reference into the Registration Statement on Form S-4/A filed on June 14, 2017, including the prospectus filed to Rule 424(b)(3) on June 19, 2017, by Bill Barrett Corporation (the “Company”) to make conforming changes to the description of the terms of the indenture governing the Company’s 8.75% Senior Notes due 2025.

Clause (2) of the definition of “Permitted Indebtedness” is hereby replaced in its entirety as follows (on page 78):

“(2) Indebtedness of the Issuer or any Restricted Subsidiary incurred to the Credit Facilities; provided, however, that immediately after giving effect to the incurrence of Indebtedness under the Credit Facilities, the aggregate principal amount of all Indebtedness incurred under this clause (2) and then outstanding does not exceed the greater of (i) $450.0 million and (ii) the Borrowing Base under the Senior Credit Facility as in effect as of the date of such incurrence; provided, that any Indebtedness incurred under this clause (2) must be secured on a basis that is or would be pari passu with the Senior Credit Facility as in effect on the date of the Indenture;”

The term “Senior Credit Facility” is hereby replaced in its entirety as follows (on page 89):

““Senior Credit Facility” means the debt facility provided for under the Third Amended and Restated Credit Agreement dated as of March 16, 2010 among Bill Barrett Corporation, as borrower, JPMorgan Chase Bank, N.A., as administrative agent, Bank of America, N.A. and Deutsche Bank Securities Inc., as syndication agents, Bank of Montreal and Wells Fargo Bank, N.A., as documentation agents and the lenders party thereto, or any successor or replacement agreements and whether by the same or any other agent, lender or group of lenders, together with the related documents thereto (including, without limitation, any guarantee agreements and security documents), in each case as such agreements may be amended (including any amendment and restatement thereof), supplemented or otherwise modified from time to time, including any agreements extending the maturity of, Refinancing, replacing, increasing or otherwise restructuring all or any portion of the Indebtedness under such agreements (provided that any increase in borrowings is permitted under clause (2) of the definition of “Permitted Indebtedness”).”

About Bill Barrett Corporation (NYSE:BBG)

Bill Barrett Corporation is an independent energy company that develops, acquires and explores for oil and natural gas resources. The Company’s assets and operations are located in the Rocky Mountain region of the United States. The Company develops oil and natural gas in the Rocky Mountain region of the United States. The Company has over two areas of production, including The Denver-Julesburg Basin (DJ Basin) and the Uinta Oil Program in the Uinta Basin. The Company’s acreage positions in the DJ Basin are located in Colorado’s eastern plains and parts of southeastern Wyoming. DJ Basin’s estimated proved reserves are 62.3 million barrels of oil equivalent (MMBoe). The Company has interests in approximately 280 gross producing wells. The Company serves as an operator in approximately 170 gross wells. The Uinta Basin is located in northeastern Utah. Uinta Basin’s estimated proved reserves are 21.4 MMBoe. Uinta Basin has interests in approximately 240 gross producing wells.