# THIRD AMENDMENT TO
CREDIT AGREEMENT

THIS THIRD AMENDMENT made as of
the 8th day of January, 2004, by and between BIOANALYTICAL SYSTEMS, INC.
("Borrower") and THE PROVIDENT BANK ("Bank");

# W I T N E S S E T H:

WHEREAS, as of October 29, 2002,
the parties hereto entered into a certain Credit Agreement, as amended (as
amended, the Agreement); and

WHEREAS, the parties desire to
further amend the Agreement to, among other things, revise certain financial
covenants and to modify the pricing, subject to the terms contained
herein;

NOW, THEREFORE, in consideration
of the premises, and the mutual promises herein contained, the parties agree
that the Agreement shall be, and it hereby is, amended as provided herein and
the parties further agree as follows:

PART I.    AMENDATORY PROVISIONS

Article 2.    Credit

2.2        
Interest; Unused Fees and Rate Selection.

| | 2.2.1    Line
of Credit  Interest.    Section 2.2.1 of the
Agreement is hereby amended by substituting the following new Section 2.2.1 in
lieu of the existing Section 2.2.1:
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| | 2.2.1    Line
of Credit  Interest.    Prior to maturity or
Default, the outstanding principal balance of Advances under the Line of Credit
shall bear interest at a per annum rate equal to the Prime Rate plus One
Percent (1%). After, and so long as, the Funded Debt Ratio is less than 3.75 to
1.00, and prior to maturity or Default, the outstanding principal balance of
Advances under the Line of Credit shall bear interest at a per annum rate equal
to the Prime Rate plus the Applicable Margin, except that at the option
of Borrower as exercised as provided in Section 2.2.4 hereof, the outstanding
principal balance of Advances under the Line of Credit in Permissible Increments
may accrue interest at the Eurodollar Rate. At the expiration of each Interest
Period, unless Borrower selects the Eurodollar Rate option as provided in
Section 2.2.4 hereof and except as otherwise provided herein, interest shall
again accrue at a per annum rate equal to the Prime Rate plus the
Applicable Margin.
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2.7        Prepayment/Exit
Fee.    Section 2.7 of the Agreement is hereby amended
by substituting September 30, 2006 in lieu of September 30,
2005 in the sixth line thereof.

Article 5.    Covenants

5.2.       
Affirmative Covenants.

| | 5.2.1        Financial
Reporting.    Section 5.2.1(e) of the Agreement is
hereby amended by substituting the following new Section 5.2.1(e) in lieu of the
existing Section 5.2.1(e):
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| | (e)        as
needed to support outstanding or requested Advances under the Line of Credit, a
Borrowing Base Certificate, in the form prescribed by Bank, executed by the
chief financial officer of Borrower, evidencing the Borrowing Base as of the
date submitted, showing the calculation thereof, the outstanding principal
amount of the Facilities (including, without limitation, Letters of Credit) and
such other information as Bank may reasonably request.
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| | 5.2.19        Full Controls/Monitoring
Fee.    Section 5.2 of the Agreement is hereby amended by
adding a new Section 5.2.19 as follows:
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| | 5.2.19    Full
Controls/Monitoring Fee.    Cause its accounts
receivable to be paid to Bank pursuant to a lockbox arrangement with Bank and
applied as collected to the Obligations, and permit the Line of Credit to be
monitored under a cash management agreement by Banks asset lending unit.
Borrower shall also pay Bank a monthly collateral monitoring fee of Seven
Hundred Fifty Dollars ($750.00), due and payable on the last Banking Day of each
month, commencing on the last Banking Day of January, 2004. Borrower also shall
grant Bank an amended and restated security agreement, in the form prescribed by
Bank, not later than January 31, 2004 to evidence and control the arrangement
provided in this Section. Borrower agrees that, notwithstanding anything
contained in the Agreement, the advance rates for Eligible Inventory and
Eligible Accounts shall be subject to change at Banks sole discretion.
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| | 5.3.1    Funded Debt
Ratio.    Section 5.3.1 of the Agreement is hereby
amended by substituting the following new Section 5.3.1 in lieu of the existing
Section 5.3.1:
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| | 5.3.1.    Funded
Debt Ratio.    Maintain its Funded Debt Ratio at not
greater than (a) 4.00 to 1.00 at each fiscal quarter ending through and
including June 30, 2004, (b) 3.50 to 1.00 as of September 30, 2004, and (c) 3.00
to 1.00 as of December 31, 2004 and at each fiscal quarter ending thereafter.
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| | 5.3.3.    Fixed Charge Coverage
Ratio.    Section 5.3.3 of the Agreement is hereby
amended by substituting the following new Section 5.3.3 in lieu of the existing
Section 5.3.3:
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| | 5.3.3.    Fixed
Charge Coverage Ratio.    Maintain its Fixed Charge
Coverage Ratio at not less than (a) 1.10 to 1.00 as of March 31, 2004 and June
30, 2004, and (b) 1.20 to 1.00 as of September 30, 2004 and at each fiscal
quarter end thereafter.
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PART II.    WAIVER

Bank hereby waives compliance by
Borrower with the provisions of Section 5.3.1 (Funded Debt Ratio) of the
Agreement for fiscal period ending December 31, 2003. This waiver shall be in
force and effect solely for the referenced period, unless otherwise agreed by
Bank in the exercise of its sole discretion.

PART III.    CONTINUING EFFECT

Except
as expressly modified herein:

| | (a)        
All terms, conditions, representations, warranties and covenants contained in
the Agreement shall remain the same and shall continue in full force and effect,
interpreted, wherever possible, in a manner consistent with this Third
Amendment; provided, however, in the event of any irreconcilable inconsistency,
this Third Amendment shall control;
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| | (b)        
The representations and warranties contained in the Agreement shall survive this
Third Amendment in their original form as continuing representations and
warranties of Borrower; and
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| | (c)        Capitalized
terms used in this Third Amendment, and not specifically herein defined, shall
have the meanings ascribed to them in the Agreement.
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In consideration hereof,
Borrower represents, warrants, covenants and agrees that:

| | (aa)        
Each representation and warranty set forth in the Agreement, as hereby amended,
remains true and correct as of the date hereof in all material respects, except
to the extent that such representation and warranty is expressly intended to
apply solely to an earlier date and except changes reflecting transactions
permitted by the Agreement;
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| | (bb)        
There currently exist no offsets, counterclaims or defenses to the performance
of the Obligations (such offsets, counterclaims or defenses, if any, being
hereby expressly waived);
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| | (cc)        
Except as expressly waived in this Third Amendment, there has not occurred any
Default or Unmatured Default; and
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| | (dd)        
After giving effect to this Third Amendment and any transactions contemplated
hereby, no Default or Unmatured Default is or will be occasioned hereby or
thereby.
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PART IV.    CONDITIONS PRECEDENT

Notwithstanding anything
contained in this Third Amendment to the contrary, Bank shall have no obligation
under this Third Amendment until each of the following conditions precedent have
been fulfilled to the satisfaction of Bank:

(a)       Each
of the conditions set forth in Section 6.2 of the Agreement shall have been
satisfied;

(b)       Bank shall have received this Third
Amendment, duly executed, and Bank shall have received the Participants Consent
attached hereto, duly executed by Fifth Third Bank (Central Indiana);

(c)       A duly executed certificate of the Secretary
or any Assistant Secretary of Borrower (A) certifying as to attached copies of
Resolutions of the Board of Directors of Borrower authorizing the execution, delivery and
performance of the Loan Documents, as amended, (B) certifying as complete and correct as
to attached copies of the Articles of Incorporation and By-Laws of Borrower or certifying
that such Articles of Incorporation or By-Laws have not been amended (except as shown)
since the previous delivery thereof to Bank;

(d)       Bank shall have received a $10,000
amendment/waiver fee from Borrower, and Borrower shall have reimbursed Bank for all legal
fees and other expenses incurred by Bank in connection with this Third Amendment and the
transactions contemplated hereby.

IN WITNESS WHEREOF, Borrower and Bank have caused this Third Amendment to be executed by
their respective officers duly authorized as of the date first above written.

| | BORROWER
BIOANALYTICAL SYSTEMS, INC.
By:  /s/ Peter T. Kissinger
Its:  Chairman and CEOBANK
THE PROVIDENT BANK
By:  /s/ Jeffrey A. Salesman
Its:  Vice President
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PARTICIPANTS CONSENT

The undersigned, the
Participant under that certain Participation Agreement dated
as of October 29, 2002 between the The Provident Bank (the
Bank) and the undersigned, hereby consents to the execution
and delivery by the Bank and Bioanalytical Systems, Inc. of the attached Third
Amendment to Credit Agreement and further consents to the terms contained
therein. The undersigned further agrees that the obligations of the undersigned
under the Participation Agreement are hereby ratified, confirmed and reaffirmed
in all respects.

IN WITNESS WHEREOF, the
undersigned has caused this Consent to be executed by its officer duly
authorized as of the 8th day of January, 2004.

| | FIFTH THIRD BANK (CENTRAL INDIANA)
(FORMERLY KNOWN AS FIFTH THIRD BANK, INDIANA
By:  /s/ M. Anderson
Its:  Vice President
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