Exhibit 10.1

THIRD AMENDMENT

TO

SECOND AMENDED AND RESTATED

CREDIT AGREEMENT

Dated as of October 20, 2008

AMONG

BILL BARRETT CORPORATION,

AS BORROWER,

THE GUARANTORS,

JPMORGAN CHASE BANK, N.A.

AS ADMINISTRATIVE AGENT,

AND

THE LENDERS PARTY HERETO

--------------------------------------------------------------------------------

THIRD AMENDMENT TO SECOND AMENDED AND RESTATED CREDIT

AGREEMENT

THIS THIRD AMENDMENT TO SECOND AMENDED AND RESTATED CREDIT AGREEMENT (this
“Third Amendment”) dated as of October 20, 2008 is among BILL BARRETT
CORPORATION, a Delaware corporation (the “Borrower”), each of the undersigned
guarantors (the “Guarantors”, and together with the Borrower, the “Obligors”)’
each of the lenders party to the Credit Agreement referred to below
(collectively, the “Lenders”), and JPMORGAN CHASE BANK, N.A., as administrative
agent for the Lenders (in such capacity, together with its successors in such
capacity, the “Administrative Agent”).

R E C I T A L S

A. The Borrower, the Administrative Agent and the Lenders are parties to that
certain Second Amended and Restated Credit Agreement dated as of March 17, 2006
(as amended by the First Amendment to Second Amended and Restated Credit
Agreement, dated November 6, 2007, the Second Amendment to Second Amended and
Restated Credit Agreement, dated March 4, 2008, and as further amended,
restated, modified or supplemented, the “Credit Agreement”), pursuant to which
the Lenders have made certain credit available to and on behalf of the Borrower.

B. The Borrower has requested and the Administrative Agent and the Lenders have
agreed to make certain other changes to the Credit Agreement.

C. NOW, THEREFORE, to induce the Administrative Agent and the Lenders to enter
into this Third Amendment and in consideration of the premises and the mutual
covenants herein contained, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

Section 1. Defined Terms. Each capitalized term used herein but not otherwise
defined herein has the meaning given such term in the Credit Agreement, as
amended by this Third Amendment. Unless otherwise indicated, all section
references in this Third Amendment refer to sections of the Credit Agreement.

Section 2. Amendments to Credit Agreement.

2.1 Amendments to Section 1.02.

(a) The following definitions are hereby added where alphabetically appropriate
to read as follows:

“‘Third Amendment’ means that certain Third Amendment to Second Amended and
Restated Credit Agreement, dated as of October 20, 2008 among the Borrower, the
Guarantors, the Administrative Agent and the Lenders party thereto.”

--------------------------------------------------------------------------------

“‘Defaulting Lender’ means a Lender (a) that fails to fund a requested Loan
required to be funded by such Lender and such default continues for a period of
three (3) Business Days, (b) that fails to reimburse the Administrative Agent
for an LC Disbursement required to be reimbursed by such Lender or (c) who (or
whose bank holding company) is placed into receivership, conservatorship or
bankruptcy.”

(b) The following are hereby amended by deleting such definitions in their
entirety and replacing them with the following:

“‘Alternate Base Rate’ means, for any day, a rate per annum equal to the
greatest of (a) the Prime Rate in effect on such day, (b) the Federal Funds
Effective Rate in effect on such day plus  1/2 of 1% and (c) the Adjusted LIBO
Rate for a one month Interest Period on such day (or if such day is not a
Business Day, the immediately preceding Business Day) plus 1%, provided that,
for the avoidance of doubt, the Adjusted LIBO Rate for any day shall be based on
the rate appearing on the Reuters BBA Libor Rates Page 3750 (or on any successor
or substitute page of such page) at approximately 11:00 a.m. London time on such
day. Any change in the Alternate Base Rate due to a change in the Prime Rate,
the Federal Funds Effective Rate or the Adjusted LIBO Rate shall be effective
from and including the effective date of such change in the Prime Rate, the
Federal Funds Effective Rate or the Adjusted LIBO Rate, respectively.”

“‘Applicable Margin’ means, for any day, with respect to any ABR or Eurodollar
Loan, the rate per annum set forth in the Borrowing Base Utilization Grid below
based upon the Borrowing Base Utilization Percentage then in effect:

 

Borrowing Base Utilization Percentage

   £50%     >50% £75%     >75% £90%     >90%  

ABR Loans

   0.25 %   0.50 %   0.75 %   1.00 %

Eurodollar Loans

   1.25 %   1.50 %   1.75 %   2.00 %

Each change in the Applicable Margin shall apply during the period commencing on
the effective date of such change and ending on the date immediately preceding
the effective date of the next such change; provided, however, that if at any
time the Borrower fails to deliver a Reserve Report pursuant to Section 8.12(a),
then the “Applicable Margin” means the rate per annum set forth on the
applicable grid when the applicable Borrowing Base Utilization Percentage is at
its highest level; provided further that the Applicable Margin shall revert to
the previous Applicable Margin upon the Borrower’s delivery of such Reserve
Report.”

 

2

--------------------------------------------------------------------------------

“‘Commitment Fee Rate’ means, for any day, the rate per annum set forth below
based upon the Borrowing Base Utilization Percentage then in effect:

 

Borrowing Base Utilization Percentage

   £50%     >50% £90%     >90%      0.350 %   0.375 %   0.500 %

Each change in the Commitment Fee Rate shall apply during the period commencing
on the effective date of such change and ending on the date immediately
preceding the effective date of the next such change; provided, however, that if
at any time the Borrower fails to deliver a Reserve Report pursuant to
Section 8.12(a), then the “Commitment Fee Rate” means the rate per annum set
forth on the applicable grid when the applicable Borrowing Base Utilization
Percentage is at its highest level; provided further that the Commitment Fee
Rate shall revert to the previous Commitment Fee Rate upon the Borrower’s
delivery of such Reserve Report.”

“‘Consolidated Net Income’ means with respect to the Borrower and the
Consolidated Subsidiaries, for any period, the aggregate of the net income (or
loss) of the Borrower and the Consolidated Subsidiaries after allowances for
taxes for such period determined on a consolidated basis in accordance with
GAAP; provided that there shall be excluded from such net income (to the extent
otherwise included therein) the following: (a) the net income of any Person in
which the Borrower or any Consolidated Subsidiary has an interest (which
interest does not cause the net income of such other Person to be consolidated
with the net income of the Borrower and the Consolidated Subsidiaries in
accordance with GAAP), except to the extent of the amount of dividends or
distributions actually paid in cash during such period by such other Person to
the Borrower or to a Consolidated Subsidiary, as the case may be; (b) the net
income (but not loss) during such period of any Consolidated Subsidiary to the
extent that the declaration or payment of dividends or similar distributions or
transfers or loans by that Consolidated Subsidiary is not at the time permitted
by operation of the terms of its charter or any agreement, instrument or
Governmental Requirement applicable to such Consolidated Subsidiary or is
otherwise restricted or prohibited, in each case determined in accordance with
GAAP; (c) the net income (or loss) of any Person acquired in a
pooling-of-interests transaction for any period prior to the date of such
transaction; (d) any extraordinary gains or losses during such period; (e) the
cumulative effect of a change in accounting principles and any gains or losses
attributable to writeups or writedowns of assets (including as a result of FAS
143) and (f) any writedowns of non-current assets, provided, however, that any
ceiling limitation writedowns under SEC guidelines shall be treated as
capitalized costs, as if such writedowns had not occurred; and provided further
that if the Borrower or any Consolidated Subsidiary shall acquire or dispose of
any Property during such period, then Consolidated Net Income shall be
calculated after giving pro forma effect to such acquisition or disposition, as
if such acquisition or disposition had occurred on the first day of such
period.”

 

3

--------------------------------------------------------------------------------

“‘EBITDAX’ means, for any period, the sum of Consolidated Net Income for such
period plus, without duplication, the following expenses or charges to the
extent deducted from Consolidated Net Income in such period: (a) income or
franchise taxes paid or accrued; (b) interest expense; (c) amortization,
depletion and depreciation expense; (d) any non-cash losses or charges resulting
from the application of FAS 133, 143 or 144; (e) oil and gas exploration and
abandonment expenses (including all drilling, completion, geological and
geophysical costs); (f) losses from sales or other dispositions of assets (other
than Hydrocarbons produced in the ordinary course of business) and other
extraordinary or non-recurring losses; (g) cash payments made during such period
as a result of the early termination of any Swap Agreement (giving effect to any
netting agreements); (h) stock based compensation resulting from application of
FAS 123R; and (i) other non-cash similar charges (excluding accruals for cash
expenses made in the ordinary course of business); minus, to the extent included
in the Consolidated Net Income for such period; (j) the sum of (i) any non-cash
gains resulting from the application of FAS 133, 143 or 144 and (ii) gains from
sales or other dispositions of assets (other than Hydrocarbons produced in the
ordinary course of business.)”

“‘LC Commitment’ at any time means forty million dollars ($40,000,000).”

“‘Majority Lenders’ means, at any time while no Loans or LC Exposure is
outstanding, Lenders having greater than fifty percent (50%) of the Aggregate
Maximum Credit Amounts; and at any time while any Loans or LC Exposure is
outstanding, Lenders holding greater than fifty percent (50%) of the outstanding
aggregate principal amount of the Loans or participation interests in Letters of
Credit (without regard to any sale by a Lender of a participation in any Loan
under Section 12.04(c)); provided that the Maximum Credit Amounts and the
principal amount of the Loans and participation interests in Letters of Credit
of the Defaulting Lenders shall be excluded from the determination of Majority
Lenders.”

“‘Required Lenders’ means, at any time while no Loans or LC Exposure is
outstanding, Lenders having at least seventy-five percent (75%) of the Aggregate
Maximum Credit Amounts; and at any time while any Loans or LC Exposure is
outstanding, Lenders holding at least seventy-five percent (75%) of the
outstanding aggregate principal amount of the Loans or participation interests
in such Letters of Credit (without regard to any sale by a Lender of a
participation in any Loan under Section 12.04(c)); provided that the Maximum
Credit Amounts and the principal amount of the Loans and participation interests
in Letters of Credit of the Defaulting Lenders shall be excluded from the
determination of Required Lenders.”

“‘Super-Majority Lenders’ means, at any time while no Loans or LC Exposure is
outstanding, Lenders having at least sixty-six and two-thirds percent (66- 2/3%)
of the Aggregate Maximum Credit Amounts; and at any time while any

 

4

--------------------------------------------------------------------------------

Loans or LC Exposure is outstanding, Lenders holding at least sixty-six and
two-thirds percent (66- 2/ 3%) of the outstanding aggregate principal amount of
the Loans or participation interests in such Letters of Credit (without regard
to any sale by a Lender of a participation in any Loan under Section 12.04(c));
provided that the Maximum Credit Amounts and the principal amount of the Loans
and participation interests in Letters of Credit of the Defaulting Lenders shall
be excluded from the determination of Super-Majority Lenders.”

2.2 Amendment to Section 3.05. Section 3.05(e) is hereby added, which section
reads in its entirety:

“(e) Defaulting Lender Fees. The Borrower shall not be obligated to pay the
Administrative Agent any Defaulting Lender’s ratable share of the fees described
in Sections 3.05(a) and (b) for the period commencing on the day such Defaulting
Lender becomes a Defaulting Lender and continuing for so long as such Lender
continues to be a Defaulting Lender.”

2.3 Amendment to Section 4.03. Section 4.03 is hereby amended to add the
following sentence to the end thereof:

If at any time prior to the acceleration or maturity of the Loans, the
Administrative Agent shall receive any payment in respect of principal of a Loan
or a reimbursement of an LC Disbursement while one or more Defaulting Lenders
shall be party to this Agreement, the Administrative Agent shall apply such
payment first to the Borrowing(s) for which such Defaulting Lender(s) shall have
failed to fund its pro rata share until such time as such Borrowing(s) are paid
in full or each Lender (including each Defaulting Lender) is owed its Applicable
Percentage of all Loans then outstanding. After acceleration or maturity of the
Loans, all principals will be paid ratably as provided in Section 10.02(c).

2.4 Amendment to Section 9.02(b). Section 9.02(b) is hereby amended by deleting
such Section in its entirety and replacing it with the following:

“(b) Debt of the Borrower and its Subsidiaries existing on October 20, 2008 that
is set forth on Schedule 9.02 attached hereto and any Permitted Refinancing
Debt.”

2.5 Amendment to Section 9.02(h). Section 9.02(h) is hereby amended by deleting
such Section in its entirety and replacing it with the following:

“(h) Permitted Debt incurred after October 20, 2008, the principal amount of
which does not exceed $300,000,000 and any guarantees thereof; provided that
(i) the Borrower shall have furnished to the Administrative Agent and the
Lenders, not less than seven Business Days prior written notice of its intent to
incur such Permitted Debt, the amount thereof, and the anticipated closing date,
together with copies of drafts of the material definitive documents therefor
and, when completed, copies of the final versions of such material definitive

 

5

--------------------------------------------------------------------------------

documents, (ii) at the time of incurring such Permitted Debt (A) no Default has
occurred and is then continuing and (B) no Default would result from the
incurrence of such Permitted Debt after giving effect to the incurrence of such
Permitted Debt (and any concurrent repayment of Debt with the proceeds of such
incurrence), (iii) the incurrence of such Permitted Debt (and any concurrent
repayment of Debt with the proceeds of such incurrence) would not result in the
total Revolving Credit Exposure exceeding the Borrowing Base then in effect,
(iv) such Permitted Debt does not have any scheduled amortization prior to the
date which is one year after the Maturity Date, (v) such Permitted Debt does not
have a scheduled maturity sooner than the date which is one year after the
Maturity Date, (vi) if such Permitted Debt is subordinated, then (A) any
guarantees thereof will be subordinated and (B) all terms of subordination are
satisfactory to the Administrative Agent and the Super Majority Lenders and
(vii) concurrently with the incurrence of such Debt, the Borrowing Base is
adjusted pursuant to Section 2.07(e).”

2.6 Amendment to Section 9.18. Section 9.18 is hereby amended by deleting such
Section in its entirety and replacing it with the following:

“Section 9.18 Swap Agreements. The Borrower will not, and will not permit any
Subsidiary to, enter into any Swap Agreements with any Person other than

(a) Swap Agreements in respect of

(i) crude oil (A) with an Approved Counterparty and (B) the notional volumes for
which do not exceed,

(1) for the three-year period following the date such Swap Agreement is
executed, the greater of (I) 70% of the reasonably anticipated projected crude
oil production from proved, probable and possible Oil and Gas Properties; and
(II) 80% of the reasonably anticipated projected crude oil production from
proved developed, producing Oil and Gas Properties, and

(2) for periods thereafter to the sixtieth month following the date such Swap
Agreement is executed, 90% of the reasonably anticipated projected crude oil
production from proved developed, producing Oil and Gas Properties, and

(3) no Swap Agreement in respect of crude oil shall have a tenor of greater than
sixty months from the date such Swap Agreement is executed;

(ii) natural gas (A) with an Approved Counterparty and (B) the notional volumes
for which do not exceed

 

6

--------------------------------------------------------------------------------

(1) for the three-year period following the date such Swap Agreement is
executed, the greater of (I) 70% of the reasonably anticipated projected natural
gas production from proved, probable and possible Oil and Gas Properties; and
(II) 80% of the reasonably anticipated projected natural gas production from
proved developed, producing Oil and Gas Properties, and

(2) for periods thereafter to the sixtieth month following the date such Swap
Agreement is executed, 90% of the reasonably anticipated projected natural gas
production from proved developed, producing Oil and Gas Properties, and

(3) no Swap Agreement in respect of natural gas shall have a tenor of greater
than sixty months from the date such Swap Agreement is executed;

(iii) the projections in subsections (i) and (ii) above will be adjusted as
follows: (A) Oil and Gas Properties evaluated in the most recently delivered
Reserve Report shall reflect the actual historical decline profile of such Oil
and Gas Properties and (B) Oil and Gas Properties not evaluated in the most
recently delivered Reserve Report shall reflect a reasonable decline profile
based upon actual historical decline profiles of similar or analogous Oil and
Gas Properties for each month during the period during which such Swap Agreement
is in effect for each of crude oil and natural gas, calculated separately,
provided, however, that for purposes of this Section 9.18(a), put options and
price floors for crude oil and natural gas shall be disregarded;

(b) Swap Agreements in respect of interest rates with an Approved Counterparty,
as follows:

(i) Swap Agreements effectively converting interest rates from fixed to
floating, the notional amounts of which (when aggregated with all other Swap
Agreements of the Borrower and its Subsidiaries then in effect effectively
converting interest rates from fixed to floating) do not exceed 50% of the then
outstanding principal amount of the Borrower’s Debt for borrowed money which
bears interest at a fixed rate, and

(ii) Swap Agreements effectively converting interest rates from floating to
fixed, the notional amounts of which (when aggregated with all other Swap
Agreements of the Borrower and its Subsidiaries then in effect effectively
converting interest rates from floating to fixed) do not exceed 75% of the then
outstanding principal amount of the Borrower’s Debt for borrowed money which
bears interest at a floating rate; and

(c) Swap Agreements permitted under (a) and (b) which are otherwise in
compliance with the Borrower’s current hedging policies which have been in
effect prior to the Effective Date or which are thereafter approved in
accordance with the policies and procedures authorized by the Borrower’s board
of directors from time to time.

 

7

--------------------------------------------------------------------------------

In no event shall any Swap Agreement (i) contain any requirement, agreement or
covenant for the Borrower or any Subsidiary to post collateral or margin to
secure their obligations under such Swap Agreement or to cover market exposures
except to the extent permitted by Section 9.03(d) or (ii) be entered into for
speculative purposes. Concurrently with the delivery of each Reserve Report, the
Borrower will furnish a projection of its reasonably anticipated projection of
natural gas and crude oil (which shall reflect the adjustments referred to
above) for the 36-month period commencing with the end of the calendar month
during which the associated Reserve Report is delivered. The Borrower may
supplement or update such projections at any time without any obligation to do
so (but subject to the representation contained in Section 7.11).

During any quarterly period, the aggregate notional volumes of all Swap
Agreements which were in effect during such period (other than basis
differential swaps) for each of natural gas and crude oil shall not exceed the
actual production volumes for each of natural gas and crude oil during such
period.”

2.7 Section 12.02(b). Clauses (ii), (vi), (vii) and (viii) of Section 12.02(b)
are hereby amended by adding the words “(other than any Defaulting Lender)”
after the words “each Lender” in each such clause.

2.8 Schedule 9.02. Schedule 9.02 attached to this Third Amendment is hereby
added to the Credit Agreement.

Section 3. Assignments; Borrowing Base.

3.1 Assignments; Additional Lenders, Increasing Lenders and Reallocation of
Commitments and Loans. The Lenders have agreed among themselves, in consultation
with the Borrower, to (i) reallocate their respective Maximum Credit Amounts and
Commitments and to, among other things, (ii) allow each of Barclays Bank plc and
Guaranty Bank and Trust Company to become a party to the Credit Agreement as an
Additional Lender by acquiring an interest in the Aggregate Maximum Credit
Amounts and Commitments and (iii) to increase the Maximum Credit Amounts and
Commitment of JPMorgan Chase Bank, N.A., Deutsche Bank Trust Company Americas,
Bank of America, N.A., U.S. Bank National Association, and Compass Bank (each,
an “Increasing Lender”). The Administrative Agent and the Borrower hereby
consent to such reallocation and each Additional Lender’s and Increasing
Lender’s acquisition of an interest in the Aggregate Maximum Credit Amounts and
Commitments. On October 20, 2008 and after giving effect to such reallocations,
the Maximum Credit Amounts and Commitment of each Lender shall be as set forth
on Annex I of this Third Amendment which Annex I supersedes and replaces the
existing Annex I to the Credit Agreement. With respect to such reallocation,
(i) each Additional Lender and each Increasing Lender shall be deemed to have
acquired the Maximum Credit Amounts and Commitment allocated to it from each of
the other Lenders pursuant to the terms of an Assignment and Assumption
Agreement in the form attached as

 

8

--------------------------------------------------------------------------------

Exhibit G to the Credit Agreement as if such New Lender, such Increasing Lender
and the other Lenders had executed an Assignment and Assumption Agreement with
respect to such allocation and (ii) upon (a) payment of the $3,500 fee to the
Administrative Agent, and (b) in the case of an Additional Lender, delivery by
such Additional Lender of (1) an Administrative Questionnaire and (2) if
necessary, delivery of any documentation required by Section 5.03(e) of the
Credit Agreement, each Additional Lender and each Increasing Lender shall be
deemed to have complied with the requirements of Section 2.06(c)(ii)(E) or
Section 2.06(c)(ii)(F), as the case may be. On October 20, 2008, the Borrower
will deliver to each Additional Lender and each Increasing Lender, a Note (or
new Note, as the case may be) payable to the order of such Lender in a principal
amount equal to its Maximum Credit Amount after giving effect to such increase,
and otherwise duly completed, and each Lender receiving a replacement Note
agrees to promptly thereafter return the previously issued Note held by such
Lender marked canceled or otherwise similarly defaced.

3.2 Borrowing Base. For the period from and including October 20, 2008 until the
next Redetermination Date, the Borrowing Base is $600,000,000. Notwithstanding
the foregoing, the Borrowing Base may be subject to further adjustments from
time to time pursuant to Section 2.07(e), Section 8.13(c), Section 9.12 or
Section 9.19.

Section 4. Conditions Precedent. This Third Amendment shall not become effective
until the date on which each of the following conditions is satisfied (or waived
in accordance with Section 12.02 of the Credit Agreement):

4.1 The Administrative Agent shall have received from each Lender, counterparts
(in such number as may be requested by the Administrative Agent) of this Third
Amendment signed on behalf of such Person.

4.2 The Administrative Agent shall have received the fees set forth in the fee
letter between the Borrower and the Administrative Agent of even date herewith.

4.3 No Default shall have occurred and be continuing as of the date hereof,
after giving effect to the terms of this Third Amendment.

4.4 The Administrative Agent shall have received such Note(s) required pursuant
to Section 3.1 of this Third Amendment.

4.5 The Administrative Agent shall have received such other documents as the
Administrative Agent or its special counsel may reasonably require.

The Administrative Agent is hereby authorized and directed to declare this Third
Amendment to be effective when it has received documents confirming or
certifying, to the satisfaction of the Administrative Agent, compliance with the
conditions set forth in this Section 4 or the waiver of such conditions as
permitted hereby. Such declaration shall be final, conclusive and binding upon
all parties to the Credit Agreement for all purposes.

 

9

--------------------------------------------------------------------------------

Section 5. Miscellaneous.

5.1 Confirmation. The provisions of the Credit Agreement, as amended by this
Third Amendment, shall remain in full force and effect following the
effectiveness of this Third Amendment.

5.2 Ratification and Affirmation; Representations and Warranties. Each Obligor
hereby (a) acknowledges the terms of this Third Amendment; (b) ratifies and
affirms its obligations under, and acknowledges, renews and extends its
continued liability under, each Loan Document to which it is a party and agrees
that each Loan Document to which it is a party remains in full force and effect,
except as expressly amended hereby, notwithstanding the amendments contained
herein and (c) represents and warrants to the Lenders that as of the date
hereof, after giving effect to the terms of this Third Amendment: (i) all of the
representations and warranties contained in each Loan Document to which it is a
party are true and correct, except to the extent any such representations and
warranties are expressly limited to an earlier date, in which case, such
representations and warranties shall continue to be true and correct as of such
specified earlier date, (ii) no Default or Event of Default has occurred and is
continuing, (iii) no event or events have occurred which individually or in the
aggregate could reasonably be expected to have a Material Adverse Effect and
(iv) the Mortgaged Properties represent at least 80% of the total value of the
Oil and Gas Properties evaluated in the most recently completed Reserve Report.

5.3 Counterparts. This Third Amendment may be executed by one or more of the
parties hereto in any number of separate counterparts, and all of such
counterparts taken together shall be deemed to constitute one and the same
instrument. Delivery of this Third Amendment by facsimile or electronic
transmission in portable document format (.pdf) shall be effective as delivery
of a manually executed counterpart hereof.

5.4 No Oral Agreement. This Third Amendment, the Credit Agreement and the other
Loan Documents executed in connection herewith and therewith represent the final
agreement between the parties and may not be contradicted by evidence of prior,
contemporaneous, or unwritten oral agreements of the parties. There are no
subsequent oral agreements between the parties.

5.5 GOVERNING LAW. THIS THIRD AMENDMENT (INCLUDING, BUT NOT LIMITED TO, THE
VALIDITY AND ENFORCEABILITY HEREOF) SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

5.6 Payment of Expenses. In accordance with Section 12.03 of the Credit
Agreement, the Borrower agrees to pay or reimburse the Administrative Agent for
all of its reasonable out-of-pocket costs and reasonable expenses incurred in
connection with this Third Amendment, any other documents prepared in connection
herewith and the transactions contemplated hereby, including, without
limitation, the reasonable fees and disbursements of counsel to the
Administrative Agent.

 

10

--------------------------------------------------------------------------------

5.7 Severability. Any provision of this Third Amendment which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.

5.8 Successors and Assigns. This Agreement shall be binding upon and inure to
the benefit of the parties hereto and their respective successors and assigns.

[SIGNATURES BEGIN NEXT PAGE]

 

11

--------------------------------------------------------------------------------

IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment to be
duly executed as of the date first written above.

 

BORROWER:     BILL BARRETT CORPORATION       By:    /s/ Fredrick J. Barrett    
    Chief Executive Officer GUARANTORS:     CIRCLE B LAND COMPANY LLC       By:
  /s/ Fredrick J. Barrett         Manager     BILL BARRETT CBM CORPORATION      
By:   /s/ Fredrick J. Barrett         Chief Executive Officer     BILL BARRETT
CBM, LLC     By:   Bill Barrett CBM Corporation, as manager       By:   /s/
Fredrick J. Barrett         Chief Executive Officer

SIGNATURE PAGE TO THIRD AMENDMENT

 

1

--------------------------------------------------------------------------------

ADMINISTRATIVE AGENT:     JPMORGAN CHASE BANK, N.A.       By:    /s/ Brian
Orlando         Name: Brian Orlando         Title: Vice President

SIGNATURE PAGE TO THIRD AMENDMENT

 

2

--------------------------------------------------------------------------------

LENDER:     JPMORGAN CHASE BANK, N.A.       By:    /s/ Brian Orlando        
Name:   Brian Orlando         Title:   Vice President     BANK OF AMERICA, N.A.
      By:    /s/ Stephen J. Hoffman       Name:   Stephen J. Hoffman      
Title:   Managing Director     DEUTSCHE BANK TRUST COMPANY AMERICAS       By:   
/s/ Dusan Lazaroy       Name:   Dusan Lazaroy       Title:   Vice President    
  By:    /s/ Erin Morrissey       Name:   Erin Morrissey       Title:   Vice
President     U.S. BANK NATIONAL ASSOCIATION       By:    /s/ Daria M. Mahoney  
    Name:    Daria M. Mahoney       Title:   Vice President

SIGNATURE PAGE TO THIRD AMENDMENT

 

3

--------------------------------------------------------------------------------

   

BMO CAPITAL MARKETS FINANCING,

INC. f/k/a Harris Nesbitt Financing, Inc.

      By:    /s/ Gumaro Tijerina       Name:   Gumaro Tijerina       Title:  
Vice President     BARCLAYS BANK plc       By:    /s/ Joseph Gyurindak      
Name:   Joseph Gyurindak       Title:   Director     FORTIS CAPITAL CORP.      
By:    /s/ David Montgomery       Name:   David Montgomery       Title:  
Director       By:    /s/ Darrell Holley       Name:   Darrell Holley      
Title:   Managing Director     WELLS FARGO BANK, N.A.       By:    /s/ Art
Krasney       Name:    Art Krasney       Title:   Vice President     BANK OF
SCOTLAND plc       By:    /s/ Julia R. Franklin       Name:    Julia R. Franklin
      Title:   Assistant Vice President

SIGNATURE PAGE TO THIRD AMENDMENT

 

4

--------------------------------------------------------------------------------

   

GE BUSINESS FINANCIAL SERVICES

INC. FKA MERRILL LYNCH BUSINESS

FINANCIAL SERVICES INC.

      By:    /s/ Randall Hornick       Name:   Randall Hornick       Title:  
Authorized Signatory     SUNTRUST BANK       By:    /s/ Yann Pirio       Name:  
Yann Pirio       Title:   Director     UNION BANK OF CALIFORNIA, N.A.       By: 
  /s/ Whitney Randolph       Name:   Whitney Randolph       Title:   Assistant
Vice President     COMPASS BANK       By:    /s/ Greg Determann       Name:   
Greg Determann       Title:   Vice President     COMERICA BANK       By:    /s/
Matt Turner       Name:    Matt Turner       Title:   Corporate Banking Officer

SIGNATURE PAGE TO THIRD AMENDMENT

 

5

--------------------------------------------------------------------------------

      CREDIT SUISSE         By:    /s/ John D. Toronto   /s/ Nupur Kumar        
Name:   John D. Toronto   Nupur Kumar         Title:  

Director

  Associate       GUARANTY BANK AND TRUST COMPANY         By:    /s/ Gail J.
Nofsinger             Name:   Gail J. Nofsinger           Title:   Senior Vice
President         GOLDMAN SACHS CREDIT PARTNERS L.P.         By:    /s/ John
Makrinos             Name:    John Makrinos           Title:   Authorized
Signatory  

SIGNATURE PAGE TO THIRD AMENDMENT

 

6

--------------------------------------------------------------------------------

ANNEX I

LIST OF MAXIMUM CREDIT AMOUNTS

Aggregate Maximum Credit Amounts

 

Name of Lender

   Applicable Percentage     Maximum Credit Amount

JPMorgan Chase Bank, N.A.

   8.3568115 %   $ 49,535,000.00

Bank of America, N.A.

   8.3568115 %     49,535,000.00

Deutsche Bank Trust Company Americas

   8.3568115 %     49,535,000.00

U.S. Bank National Association

   8.3568115 %     49,535,000.00

BMO Capital Markets Financing, Inc.

   7.5917334 %     45,000,000.00

Barclays Bank plc

   6.7482075 %     40,000,000.00

Fortis Capital Corp.

   6.7482075 %     40,000,000.00

Wells Fargo Bank, N.A.

   6.7482075 %     40,000,000.00

Bank of Scotland plc

   5.7823703 %     34,275,000.00

GE Business Financial Services Inc.

   5.7823703 %     34,275,000.00

SunTrust Bank

   5.7823703 %     34,275,000.00

Union Bank of California, N.A.

   5.7823703 %     34,275,000.00

Compass Bank

   4.6410797 %     27,510,000.00

Comerica Bank

   4.2176297 %     25,000,000.00

Credit Suisse

   4.2176297 %     25,000,000.00

Guaranty Bank and Trust Company

   1.6870519 %     10,000,000.00

Goldman Sachs Credit Partners L.P.

   0.8435259 %     5,000,000.00

TOTAL

   100 %   $ 592,750,000.00

 

ANNEX I

--------------------------------------------------------------------------------

SCHEDULE 9.02

EXISTING DEBT

$172,500,000 5% Convertible Senior Notes due 2028

 

SCHEDULE 9.02