Exhibit 10.23
 
LENDER JOINDER AGREEMENT
 
THIS LENDER JOINDER AGREEMENT (this “Agreement”) dated as of June 28, 2002 to
the Credit Agreement referenced below is by and among WACHOVIA BANK, NATIONAL
ASSOCIATION (the “New Lender”), AMERIGROUP CORPORATION, a Delaware corporation
(the “Borrower”), certain Subsidiaries and Affiliates of the Borrower, as
Guarantors, and BANK OF AMERICA, N.A., as administrative agent (in such
capacity, the “Administrative Agent”) for the Lenders. All of the defined terms
of the Credit Agreement are incorporated herein by reference.
 
W I T N E S S E T H
 
WHEREAS, pursuant to that Credit and Guaranty Agreement dated as of December 14,
2001 (as amended and modified from time to time, the “Credit Agreement”) among
the Borrower, the Guarantors, the Lenders and the Administrative Agent, the
Lenders have agreed to provide the Borrower with a $60 million revolving credit
facility;
 
WHEREAS, pursuant to Section 2.1(d) of the Credit Agreement, the Borrower has
requested that the New Lender provide an additional Revolving Commitment under
the Credit Agreement; and
 
WHEREAS, the New Lender has agreed to provide the additional Revolving
Commitment on the terms and conditions set forth herein and to become a “Lender”
under the Credit Agreement in connection therewith;
 
NOW, THEREFORE, IN CONSIDERATION of the premises and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:
 
1.    The New Lender hereby agrees to provide Commitments to the Borrower in the
amounts set forth on Schedule 2.1(a) to the Credit Agreement as attached hereto.
The Revolving Commitment Percentage of the New Lender shall be as set forth on
Schedule 2.1(a).
 
2.    The New Lender shall be deemed to have purchased without recourse a risk
participation from the Issuing Lender in all Letters of Credit issued or
existing under the Credit Agreement (including Existing Letters of Credit) and
the obligations arising thereunder in an amount equal to its pro rata share of
the obligations under such Letters of Credit (based on the Revolving Commitment
Percentages of the Lenders as set forth on Schedule 2.1(a) as attached hereto),
and shall absolutely, unconditionally and irrevocably assume, as primary obligor
and not as surety, and be obligated to pay to the Issuing Lender therefor and
discharge when due, its pro rata share of the obligations arising under such
Letter of Credit.
 
3.    The New Lender (a) represents and warrants that it is a commercial lender,
other financial institution or other “accredited” investor (as defined in SEC
Regulation D) that makes or acquires loans in the ordinary course of business
and that it will make or acquire Loans for its own account in the ordinary
course of business, (b) confirms that it has received a copy of the Credit
Agreement, together with copies of the financial statements referred to in
Section 7.1 thereof and such other documents and information as it has deemed
appropriate to make its own credit analysis and decision to enter into this
Agreement; (c) agrees that it will, independently and without reliance upon the
Administrative Agent or any other Lender and based on such documents and
information as it shall deem appropriate at the time, continue to make its own
credit decisions in taking or not taking action under the Credit Agreement; (d)
appoints and authorizes the Administrative Agent to take such action as agent on
its behalf and to exercise such

1

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

 
powers and discretion under the Credit Agreement as are delegated to the
Administrative Agent by the terms thereof, together with such powers and
discretion as are reasonably incidental thereto; and (e) agrees that, as of the
date hereof, the New Lender shall (i) be a party to the Credit Agreement and the
other Credit Documents, (ii) be a “Lender” for all purposes of the Credit
Agreement and the other Credit Documents, (iii) perform all of the obligations
that by the terms of the Credit Agreement are required to be performed by it as
a “Lender” under the Credit Agreement and (iv) shall have the rights and
obligations of a Lender under the Credit Agreement and the other Credit
Documents.
 
4.    Each of the Borrower and the Guarantors agrees that, as of the date
hereof, the New Lender shall (i) be a party to the Credit Agreement and the
other Credit Documents, (ii) be a “Lender” for all purposes of the Credit
Agreement and the other Credit Documents, and (iii) have the rights and
obligations of a Lender under the Credit Agreement and the other Credit
Documents.
 
5.    The address of the New Lender for purposes of all notices and other
communications is Wachovia Bank, National Association, 101 W. Main St., Norfolk,
VA 23510, Attention of Don Clark (Facsimile No. 757-640-5690).
 
6.    This Agreement may be executed in any number of counterparts and by the
various parties hereto in separate counterparts, each of which when so executed
shall be deemed to be an original and all of which taken together shall
constitute one contract. Delivery of an executed counterpart of this Agreement
by telecopier shall be effective as delivery of a manually executed counterpart
of this Agreement.
 
7.    This Agreement shall be governed by and construed and interpreted in
accordance with the laws of the State of New York.
 
[remainder of page intentionally left blank]
 

2

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

 
IN WITNESS WHEREOF, each of the parties hereto has caused this Agreement to be
executed by a duly authorized officer as of the date first above written.
 
NEW LENDER:
WACHOVIA BANK, NATIONAL ASSOCIATION

 
By:    /s/  Todd J. Eagle
Name:    Todd J. Eagle
Title:    Vice President
 
BORROWER:
AMERIGROUP CORPORATION, a Delaware corporation

 
By:    /s/  Sherri E. Lee
Name:    Sherri E. Lee
Title:    SVP and Treasurer
 
GUARANTORS:
[NONE AS OF THE DATE HEREOF]

 
Accepted and Agreed:
 
BANK OF AMERICA, N.A.,
as Administrative Agent
 
By:    /s/  Gary Flieger
Name:    Gary Flieger
Title:    Vice President
 

3

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

Schedule 2.1(a)
 
LENDERS AND COMMITMENTS
 
Revolving Commitments
 
Lender

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

    
Revolving
Commitment
Percentage

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

    
Revolving
Committed
Amount

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

    
LOC
Committed
Amount

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

Bank of America, N.A.
    
33.333333%
    
$25,000,000.00
    
$  4,999,999.95
UBS AG, Stamford Branch
    
26.666667%
    
$20,000,000.00
    
$  4,000,000.05
CIBC Inc.
    
20.000000%
    
$15,000,000.00
    
$  3,000,000.00
Wachovia Bank, National Association
    
20.000000%
    
$15,000,000.00
    
$  3,000,000.00
      

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

    

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

    

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

Total
    
100.000000%
    
$75,000,000.00
    
$15,000,000.00

4