PROMISSORY
NOTE

      (FIXED
RATE)

      


      
        	
                $1,500,000.00

              	
                San
      Antonio, Texas

              	
                November
      19, 2009

              


      

      


      The
undersigned, SOUTH TEXAS OIL COMPANY, a Nevada corporation, STO DRILLING
COMPANY, a Texas corporation, STO OPERATING COMPANY, a Texas corporation, STO
PROPERTIES, LLC, a Texas limited liability company, and SOUTHERN TEXAS OIL
COMPANY, a Texas corporation ("Borrower"),
for value received, jointly and severally, if more than one, promises and agrees
to pay to the order of GIDDINGS INVESTMENTS LLC, a Delaware limited liability
company (hereinafter called "Lender"),
or other holder hereof, at 3 Parklands Drive, Suite 102, Darien, CT 06820, Attn:
Greg Imbruce, in lawful money of the United States of America, the principal sum
of ONE MILLION FIVE HUNDRED THOUSAND AND NO/100 DOLLARS ($1,500,000.00) (or the
unpaid balance of all principal advanced against this Note, if that amount is
more or less), together with interest thereon at the rate specified below;
provided, however, that in no event shall the rate specified below, together
with all other consideration contracted for, charged or received by the holder
of this Note which constitutes interest under applicable law, exceed the amount
of interest which could be charged at the Highest Lawful Rate.

       

      1.            
Definitions. As used in
this Note, the following terms shall have the meanings assigned:

       

      “Business Day” means a day
other than a Saturday, Sunday, or other day on which banks in San Antonio, Texas
or New York, New York are required or authorized to be closed.

       

      “Event of Default” shall have
the meaning assigned to such term in the Loan Agreement.

       

      “Governmental Authority” means
any foreign governmental authority, the United States, and any political
subdivision of any of them, whether state, provincial, or local, and any agency,
department, commission, board, bureau, court or other tribunal, or
instrumentality of any of them which now or hereafter has jurisdiction over
Lender (or any participant herein) or a Borrower or a Borrower’s
assets.

       
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      “Highest Lawful Rate” shall
mean on any day, the maximum nonusurious rate of interest permitted for that day
by whichever of applicable federal or Texas law permits the higher interest
rate, stated as a rate per annum.  On each day, if any, that the Texas
Finance Code, as supplemented by art. 1D.003 of the Texas Credit Title, as it
may from time to time be amended (the “Texas
Credit Code”), establishes the Highest Lawful Rate, the Highest Lawful
Rate shall be the “weekly rate ceiling”, as referred to in Section 303.002 of
the Texas Finance Code, after application of Section 303.009 of the Texas
Finance Code, for that day.  Provided, however, that to the extent
permitted by applicable law, Lender reserves the right to change, from time to
time by further notice and disclosure to a Borrower, the ceiling on which the
Highest Lawful Rate is based under the Texas Finance Code, and, provided
further, that the “highest non-usurious rate of interest permitted by applicable
law” for purposes of this Note shall not be limited to the applicable rate
ceiling under the Texas Finance Code if federal laws or other state laws now or
hereafter in effect and applicable to this Note (and the interest contracted
for, charged and collected thereunder) shall permit a higher rate of
interest.

       

      “Legal Requirement” means any
law, statute, ordinance, decree, order, ruling, requirement, judgment, rule or
regulation (or authoritative interpretation of any of them) of any Governmental
Authority, and the terms of any license, permit, consent or approval issued by
any Governmental Authority.

       

      “Loan Agreement” means the
Debtor-in-Possession Loan and Security Agreement, of even date herewith, by and
between Borrower and Lender, as may be amended, restated, supplemented, and
modified from time to time.

       

      “Maturity Date” means January
31, 2010.

       

      “Past Due Rate” means the
lesser of (a) the rate of five percent (5%) per annum plus the interest rate set
forth in Section 2(a) of this Note or (b) the Highest Lawful Rate.

       

       “Regulation D” means
Regulation D of the Board of Governors of the Federal Reserve System from time
to time in effect and shall include any successor or other regulation relating
to reserve requirements applicable to member banks of the Federal Reserve
System.

       

      2.            
Interest.  Interest
shall accrue on the outstanding principal balance of this Note, or any portion
hereof, as follows:

       

      
        
          	
                	
                  (a)

                	
                  Subject
      to the applicable provisions of this Note, commencing on the date hereof
      up to and including the Maturity Date, at a rate of ten percent (10%) per
      annum; and

                


        

      

       

      
        
          	
                	
                  (b)

                	
                  All
      past due principal and interest shall bear interest from its due date
      until paid at the Past Due Rate (after as well as before
      judgment).

                


        

      

       

      3.            
Payments of Principal and
Interest.

       

      3.1           This
Note shall be due and payable as follows:

       
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                (a)

              	
                Accrued
      and unpaid interest on the principal of this Note for the immediately
      preceding month shall be due and payable on the fifth day of each month
      commencing on December 5, 2009; and

              


      

       

      
        	
                 
      

              	
                (b)

              	
                The
      entire unpaid principal sum of this Note and all interest accrued and
      unpaid thereon shall be fully and finally due and payable on the Maturity
      Date.

              


      

       

      3.2           All
payments hereon shall be credited first to past due accrued interest and then to
principal; and interest shall thereupon cease upon the principal so
credited.

       

      3.3           All
payments made by a Borrower on this Note shall be made to Lender at its address
set forth in this Note (or otherwise designated by Lender) in federal or other
immediately available funds before 1:00 p.m., San Antonio, Texas time, on the
date such payment is required to be made.  Any payment received and
accepted by Lender after such time shall be considered for all purposes
(including the calculation of interest, to the extent permitted by law) as
having been made on the next following Business Day.

       

      3.4           This
Note is not a revolving note.  An amount borrowed may not be repaid
and reborrowed. Further, no advances shall be made under this Note except in
accordance with the Loan Agreement.

       

      4.           
INDEMNIFICATION.  EACH BORROWER AGREES TO INDEMNIFY
LENDER AND ANY PARTICIPANT AGAINST AND HOLD LENDER AND ANY PARTICIPANT HARMLESS
FROM ANY LOSS OR EXPENSE WHICH LENDER AND ANY PARTICIPANT MAY INCUR OR SUSTAIN
AS A CONSEQUENCE OF ANY LATE PAYMENT (MANDATORY OR OPTIONAL) OR DEFAULT BY A
BORROWER IN THE PAYMENT OF ANY PRINCIPAL AMOUNT OF OR INTEREST ON THIS
NOTE.  A CERTIFICATE AS TO ANY ADDITIONAL AMOUNTS PAYABLE PURSUANT TO
THIS PARAGRAPH SUBMITTED BY LENDER TO BORROWER SHALL BE MADE BY LENDER IN GOOD
FAITH, SHALL CONTAIN REASONABLE DETAIL OF LENDER’S CALCULATION, AND SHALL BE
CONCLUSIVE AND BINDING UPON BORROWER, ABSENT MANIFEST ERROR.  THE
INDEMNITY AGREEMENTS CONTAINED IN THIS NOTE SHALL SURVIVE THE PAYMENT OF THIS
NOTE AS TO ANY AMOUNTS OR OBLIGATIONS ACCRUED HERE UNDER PRIOR TO THE LATER OF
PAYMENT OF THIS NOTE IN FULL.

       

      5.           
Prepayment.  Borrower
shall have the right at any time and from time to time upon at least three
Business Days’ irrevocable written notice to Lender, to prepay any sums due
under this Note in whole or in part.  For any prepayment, Borrower in
its notice shall specify the date proposed for prepayment (each, a “Prepayment
Date”) and the principal amount to be prepaid.  Whenever notice
of any such prepayment has been given, the principal amount to be prepaid
together with all accrued interest thereon shall automatically become due and
payable at or before 1:00 p.m., San Antonio time, on such Prepayment
Date.

       
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      6.           
Loan
Agreement.  This Note is issued pursuant to and in accordance
with the terms and provisions of the Loan Agreement.  This Note is the
Note under and as defined in the Loan Agreement.  This Note is secured
by, among other things, the Collateral under and as defined in the Loan
Agreement.

       

      7.           
Default.  This
Note shall become immediately due and payable, at the option of Lender or other
holder hereof, without presentment or demand or any notice to Borrower or any
other person obligated or to become obligated hereon, upon the occurence of an
Event of Default.

       

      8.          
 Expenses.  Upon the
occurrence of an Event of Default under and as defined in the Loan Agreement,
and this Note is placed in the hands of an attorney for collection (whether or
not suit is filed), or if this Note is collected by suit or legal proceedings or
through the probate court or bankruptcy proceedings, Borrower agrees to pay an
additional reasonable amount as attorney's fees and expenses of
collection.

       

      9.           
Waivers.  Except for
the notices specifically set forth in and required by the Loan Agreement,
Borrower and all sureties, endorsers, and guarantors of this Note (i) waive
presentment for payment, protest and demand, notice of nonpayment, notice of
protest, demand, dishonor, nonpayment, default, notice of intent to accelerate,
notice of acceleration, and diligence in collecting this Note or enforcing any
of the security herefor, (ii) agree to any substitution, exchange or release of
any such security or the release of any party primarily or secondarily liable
hereon, (iii) agree that Lender or other holder hereof shall not be required
first to institute suit or exhaust its remedies hereon against a Borrower or
others liable or to become liable hereon in order to enforce payment of this
Note by them, and (iv) consent to any extension or postponement of time of
payment of this Note without notice thereof to any of them.

       

      10.           Controlling
Agreement.  No provisions of this Note or any instrument
securing payment hereof or otherwise relating to the debt evidenced hereby shall
require the payment or permit the charging, collection, application or receipt
of interest in excess of interest calculated at the Highest Lawful
Rate.  If any excess of interest in such respect is herein or in any
such other instrument provided for, charged, or received, or shall be
adjudicated to be so provided for herein or in any such instrument, the
provisions of this paragraph shall govern, and neither a Borrower nor any
endorsers of this Note nor their respective heirs, personal representatives,
successors or assigns shall be obligated to pay the amount of such interest to
the extent it is in excess of interest calculated at the Highest Lawful
Rate.  It is expressly stipulated and agreed to be the intent of any
Borrower and holder to at all times comply with the usury and other laws
relating to this Note and the other instruments securing payment hereof now or
hereafter in effect, and any subsequent revisions, repeals, or judicial
interpretations thereof, to the extent that any of the same are applicable
hereto or to the other instruments securing payment hereof.  In the
event Lender or other holder hereof ever contracts for, charges, receives,
collects or applies as interest any such excess, such amount which would be
excessive interest shall be applied to the reduction of the unpaid principal
balance of this Note, and, if upon such application the principal balance of
this Note is paid in full, any remaining excess shall be forthwith paid to a
Borrower and the provisions of this Note and the other instruments securing
payment hereof shall immediately be deemed reformed and the amounts thereafter
collectible hereunder and thereunder reduced, without the necessity of execution
of any new documents, so as to comply with the then applicable law, but so as to
permit the recovery of the fullest amount otherwise called for hereunder and
thereunder.  In determining whether or not the interest paid or
payable under any specific contingency exceeds the Highest Lawful Rate, each
Borrower and Lender or other holder hereof shall, to the maximum extent
permitted under applicable law, amortize, prorate, allocate and spread the total
amount of interest throughout the entire term of this Note so that the amount or
rate of interest contracted for, charged or received for any and all periods of
time during the term of this Note is to the greatest extent possible less than
the maximum amount or rate of interest allowed to be charged by law during the
relevant period of time.  Notwithstanding any of the foregoing, if at
any time applicable laws shall be changed so as to permit a higher rate or
amount of interest to be charged than that permitted prior to such change, then
unless prohibited by law, references in this Note to "applicable law" for
purposes of determining the maximum interest or rate of interest which can be
charged shall be deemed to refer to such applicable laws as so amended to allow
the greater amount or rate of interest.

       
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      11.           Temporary
Waiver.  If there is any Event of Default under the terms of
the Loan Agreement, and the holder hereof temporarily waives or fails to
immediately exercise its rights under the Loan Agreement, such waiver shall not
be construed either as extending beyond such temporary waiver or as extending to
any subsequent Event of Default.

       

      12.           APPLICABLE
LAWS.  THIS
NOTE HAS BEEN EXECUTED AND DELIVERED IN AND SHALL BE CONSTRUED IN ACCORDANCE
WITH AND GOVERNED BY THE LAWS OF THE STATE OF TEXAS AND OF THE UNITED STATES OF
AMERICA FROM TIME TO TIME IN EFFECT.  HARRIS COUNTY, TEXAS SHALL BE A
PROPER PLACE OF VENUE FOR SUIT HEREON.  BORROWER AND ANY AND ALL
CO-MAKERS, ENDORSERS, GUARANTORS AND SURETIES IRREVOCABLY AGREE THAT ANY LEGAL
PROCEEDINGS IN RESPECT OF THIS NOTE OR ANY DOCUMENT EXECUTED IN CONNECTION
HEREWITH SHALL BE BROUGHT IN THE DISTRICT COURTS OF BEXAR COUNTY, TEXAS, OR THE
UNITED STATES DISTRICT COURT FOR THE WESTERN DISTRICT OF TEXAS, SAN ANTONIO
DIVISION.

       

      13.           NOTICE OF FINAL
AGREEMENT.  THIS NOTE AND THE OTHER DOCUMENTS
EXECUTED SUBSTANTIALLY CONTEMPORANEOUSLY HEREWITH REPRESENT THE FINAL AGREEMENT
BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS OF THE PARTIES.

      


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                                                                                    SOUTH
      TEXAS OIL COMPANY,

                                                                                  
	
                                                                                    a
      Nevada corporation

                                                                                  
	
                                                                                      /s/
      Michael J. Pawelek

                                                                                  
	
                                                                                    By:

                                                                                  	 
      
	
                                                                                    Name:
      Michael J. Pawelek

                                                                                  
	
                                                                                    Title:
      CEO. President

                                                                                  
	 
      	 
      
	
                                                                                    STO
      DRILLING COMPANY,

                                                                                  
	
                                                                                    a
      Texas corporation

                                                                                  
	
                                                                                      /s/
      Michael J. Pawelek

                                                                                  
	
                                                                                    By:

                                                                                  	 
      
	
                                                                                    Name:
      Michael J. Pawelek

                                                                                  
	
                                                                                    Title:
      CEO. President

                                                                                  
	 
      	 
      
	
                                                                                    STO
      OPERATING COMPANY,

                                                                                  
	
                                                                                    a
      Texas corporation

                                                                                  
	
                                                                                      /s/
      Wayne A. Psencik

                                                                                  
	
                                                                                    By:

                                                                                  	 
      
	
                                                                                    Name:
      Wayne A. Psencik

                                                                                  
	
                                                                                    Title:
      President

                                                                                  
	 
      	 
      
	
                                                                                    STO
      PROPERTIES, LLC,

                                                                                  
	
                                                                                    a
      Texas limited liability company

                                                                                  
	
                                                                                      /s/
      Wayne A. Psencik

                                                                                  
	
                                                                                    By:

                                                                                  	 
      
	
                                                                                    Name:
      Wayne A. Psencik

                                                                                  
	
                                                                                    Title:
      Manager

                                                                                  
	 
      	 
      
	
                                                                                    SOUTHERN
      TEXAS OIL COMPANY,

                                                                                  
	
                                                                                    a
      Texas corporation

                                                                                  
	
                                                                                      /s/
      Michael J. Pawelek

                                                                                  
	
                                                                                    By:

                                                                                  	 
      
	
                                                                                    Name:
      Michael J. Pawelek

                                                                                  
	
                                                                                    Title:
      CEO.
President

                                                                                  


                                                                          

                                                                        

                                                                      

                                                                    

                                                                  

                                                                

                                                              

                                                            

                                                          

                                                        

                                                      

                                                    

                                                  

                                                

                                              

                                            

                                          

                                        

                                      

                                    

                                  

                                

                              

                            

                          

                        

                      

                    

                  

                

              

            

          

        

      

      


      ACKNOWLEDGED
FOR PURPOSES OF SECTION

      26.02 OF
THE TEXAS BUSINESS AND

      


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                                COMMERCE
      CODE BY:

                              
	 
      	 
      
	
                                GIDDINGS
      INVESTMENTS LLC,

                              
	
                                a
      Delaware limited liability company

                              
	 
      	 
      
	
                                  /s/
      Greg Imbruce

                              
	
                                By:

                              	 
      
	
                                Name:  Greg
      Imbruce

                              
	
                                Title:
      President

                              


                      

                       

                    

                  

                

              

            

          

        

      
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