SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON, D.C.   20549

                                       FORM 8-A

                 FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES

                     PURSUANT TO SECTION 12(b) OR 12(g) OF THE

                          SECURITIES EXCHANGE ACT OF 1934
                                           

                               PENNACO ENERGY, INC. 
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                (Exact name of registrant as specified in its charter)
                                           
     
                NEVADA                                  88-0384598 
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(State of incorporation or organization)   (I.R.S. Employer Identification No.)

     
            1050 17TH STREET
               SUITE 700
            DENVER, COLORADO                              80265
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(Address of principal executive office)                 (Zip Code)


SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

         TITLE OF EACH CLASS                   NAME OF EACH EXCHANGE ON WHICH
         TO BE SO REGISTERED                   EACH CLASS IS TO BE REGISTERED
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    Common Stock, par value $.001                  American Stock Exchange
   Rights to Purchase Common Stock                 American Stock Exchange 

     If this form relates to the registration of a class of securities pursuant
to Section 12(b) of the Exchange Act and is effective pursuant to General
Instruction A.(c), check the following box.  /X/

     If this form relates to the registration of a class of securities pursuant
to Section 12(g) of the Exchange Act and is effective pursuant to General
Instruction A.(d), check the following box. / /

     Securities Act registration statement file number to which this form
relates: __________ (if applicable)

SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:

                                          None  
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                                    (Title of Class) 


ITEM 1.  DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

SUMMARY OF THE COMMON STOCK

   A description of the common stock, par value $0.001 per share, of 
Pennaco Energy, Inc. (the "Company") to be registered hereunder is set forth 
under Item 8 -- "Description of Securities" in the prospectus included in the 
Registrant's Registration Statement on Form 10-SB, as amended (File No. 
000-24881), initially filed with the Securities and Exchange Commission on 
September 8, 1998, under the Securities Exchange Act of 1934, as amended, 
which description is incorporated herein by reference. 

SUMMARY OF RIGHTS TO PURCHASE COMMON STOCK

   On February 24, 1999, the Board of Directors of the Company declared a 
dividend distribution of one common stock purchase right (a "Right") for each 
outstanding share of Common Stock of the Company.  The distribution is 
payable to the stockholders of record at the close of business on March 9, 
1999 (the "Record Date").  Each Right entitles the registered holder thereof 
to purchase from the Company one-half of a share of Common Stock, at a price 
of $20, subject to adjustment.  The following is a summary of the Rights; the 
full description and terms of the Rights are set forth in a Rights Agreement 
(the "Rights Agreement") between the Company and Harris Trust and Savings 
Bank, as Rights Agent (the "Rights Agent"). Copies of the Rights Agreement 
are available free of charge from the Company. This summary description of 
the Rights does not purport to be complete and is qualified in its entirety 
by reference to all the provisions of the Rights Agreement, including the 
definitions therein of certain terms, which Rights Agreement is incorporated 
herein by reference.

   THE RIGHTS AGREEMENT

   Initially, the Rights will attach to all certificates representing shares 
of outstanding Company Common Stock, and no separate Rights Certificates will 
be distributed. The Rights will separate from the Company Common Stock and 
the Distribution Date will occur upon the earlier of (i) 10 days following 
the date of public announcement that a person or group of persons has become 
an Acquiring Person (as hereinafter defined) or (ii) 10 business days (or 
such later date as may be determined by action of the Board of Directors 
prior to the time a person becomes an Acquiring Person) following the 
commencement of, or the announcement of an intention to make, a tender offer 
or exchange offer upon consummation of which the offeror would, if 
successful, become an Acquiring Person (the earlier of such dates being 
called the "Distribution Date").

   The term "Acquiring Person" means any person who or which, together with 
all of its affiliates and associates, shall be the beneficial owner of 15% or 
more of the outstanding Common Stock, but shall not include (i) the Company 
or any Subsidiary of the Company or any employee benefit plan of the Company 
or (ii) R.I.S. Resources International Corp. and its subsidiaries 
(collectively, "RIS") or any other person or entity in which RIS is at the 
time of determination the direct record and beneficial of all outstanding 
voting securities (collectively, "Exempt Persons").

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   The Rights Agreement provides that, until the Distribution Date, the 
Rights will be transferred with and only with the Common Stock.  Until the 
Distribution Date (or earlier redemption or expiration of the Rights), new 
Common Stock certificates issued after the Record Date, upon transfer or new 
issuance of Common Stock, will contain a notation incorporating the Rights 
Agreement by reference.  Until the Distribution Date (or earlier redemption 
or expiration of the Rights), the surrender for transfer of any certificates 
for Common Stock, outstanding as of the Record Date, even without such 
notation or a copy of this Summary of Rights being attached thereto, will 
also constitute the transfer of the Rights associated with the Common Stock 
represented by such certificate.  As soon as practicable following the 
Distribution Date, separate certificates evidencing the Rights ("Rights 
Certificates") will be mailed to holders of record of the Common Stock as of 
the close of business on the Distribution Date and such separate Rights 
Certificates alone will evidence the Rights.

   The Rights are not exercisable until the Distribution Date.  The Rights 
will expire on March 9, 2009 (the "Expiration Date").

   The Purchase Price payable, and the number of one-half of a share of 
Common Stock or other securities or property issuable, upon exercise of the 
Rights are subject to adjustment from time to time to prevent dilution (i) in 
the event of a stock dividend on, or a subdivision, combination or 
reclassification of, the Common Stock, (ii) upon the grant to holders of the 
Common Stock of certain rights or warrants to subscribe for or purchase 
shares of Common Stock at a price, or securities convertible into Common 
Stock with a conversion price, less than the then current market price of the 
Common Stock or (iii) upon the distribution to holders of the Common Stock of 
evidences of indebtedness or assets (excluding regular periodic cash 
dividends paid or dividends payable in Common Stock) or of subscription 
rights or warrants (other than those referred to in (ii) above).

   The number of outstanding Rights and the number of one-half of a share of 
Common Stock issuable upon exercise of each Right are also subject to 
adjustment in the event of a stock split of the Common Stock or a stock 
dividend on the Common Stock payable in the Common Stock or subdivisions, 
consolidations or combinations of the Common Stock occurring, in any such 
case, prior to the Distribution Date.

   In the event that following a Stock Acquisition Date (the date of public 
announcement that an Acquiring Person has become such) the Company is 
acquired in a merger or other business combination transaction or more than 
50% of its consolidated assets or earning power are sold, proper provision 
will be made so that each holder of a Right will thereafter have the right to 
receive, upon the exercise thereof at the then current exercise price of the 
Right, that number of shares of common stock of the acquiring company which 
at the time of such transaction will have a market value of two times the 
exercise price of the Right (the "Flip-Over Right").

   In the event that a person (other than an Exempt Person) becomes an 
Acquiring Person, proper provision shall be made so that each holder of a 
Right (other than the Acquiring Person and its affiliates and associates) 
will thereafter have the right to receive upon exercise that number of shares 
of Common Stock (or, under certain circumstances, cash, other equity 
securities or property of the 

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Company) having a market value equal to two times the Purchase Price of the
Rights (the "Flip-In Right").  Upon the occurrence of the foregoing event giving
rise to the exercisability of the Rights, any Rights that are or were at any
time owned by an Acquiring Person shall become void.

   With certain exceptions, no adjustment in the Purchase Price will be 
required until cumulative adjustments require an adjustment of at least 1% in 
such Purchase Price.  Upon exercise of the Rights, no fractional shares of 
Common Stock will be issued and cash will be paid in lieu of fractional 
shares of Common Stock.

   At any time prior to the earlier to occur of (i) 5:00 p.m., Houston, Texas 
time, on the 10th day after the Stock Acquisition Date or (ii) the expiration 
of the Rights, the Company may redeem the Rights in whole, but not in part, 
at a price of $0.01 per Right (the "Redemption Price"); PROVIDED, that (i) if 
the Board of Directors authorizes redemption on or after the time a person 
becomes an Acquiring Person, then such authorization must be by Board 
Approval (as hereinafter defined) and (ii) the period for redemption may, 
upon Board Approval, be extended by amending the Rights Agreement.  The term 
"Board Approval" means the approval of a majority of the directors of the 
Company. Immediately upon any redemption of the Rights described in this 
paragraph, the right to exercise the Rights will terminate and the only right 
of the holders of Rights will be to receive the Redemption Price.

   The terms of the Rights may be amended by the Board of Directors without 
the consent of the holders of the Rights at any time and from time to time 
provided that such amendment does not adversely affect the interests of the 
holders of the Rights.  In addition, during any time that the Rights are 
subject to redemption, the terms of the Rights may be amended by Board 
Approval, including an amendment that adversely affects the interests of the 
holders of the Rights, without the consent of the holders of Rights.

   Until a Right is exercised, the holder thereof, as such, will have no 
rights as a stockholder of the Company, including, without limitation, the 
right to vote or to receive dividends.  While the distribution of the Rights 
will not be taxable to stockholders or to the Company, stockholders may, 
depending upon the circumstances, recognize taxable income in the event that 
the Rights become exercisable for Common Stock (or other consideration).

ITEM 2.  EXHIBITS.

     The following exhibits to this Registration Statement on Form 8-A are
either filed herewith or are incorporated by reference from the documents
specified, which have been filed with the Securities and Exchange Commission.


       
     1.   The Company's Registration Statement on Form 10-SB (File No.
          000-24881), as amended, filed with the Securities and Exchange
          Commission on September 8, 1998 (the "Registration Statement")
          (incorporated herein by reference).

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     2.   Articles of Incorporation of the Company (incorporated herein by
          reference to Exhibit 3.1 to the Registration Statement).

     3.   Bylaws of the Company (incorporated herein by reference to Exhibit 3.2
          to the Registration Statement).

    *4.   Rights Agreement, dated February 24, 1999, between the
          Company and Harris Trust and Savings Bank, as Rights Agent.

    *5.   Specimen Certificate representing Common Stock of the Registrant.

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* FILED HEREWITH
 

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                                      SIGNATURE

     Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the Registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereunto duly authorized.

Dated: April 16, 1999

                                          PENNACO ENERGY, INC.


                                          /s/ Glen C. Warren, Jr.
                                          --------------------------------------
                                          Glen C. Warren, Jr.
                                          CHIEF FINANCIAL OFFICER AND EXECUTIVE 
                                          VICE PRESIDENT






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                                    EXHIBIT INDEX


       
     1.   The Company's Registration Statement on Form 10-SB (File No.
          000-24881), as amended, filed with the Securities and Exchange
          Commission on September 8, 1998 (the "Registration Statement")
          (incorporated herein by reference).

     2.   Articles of Incorporation of the Company (incorporated herein by
          reference to Exhibit 3.1 to the Registration Statement).

     3.   Bylaws of the Company (incorporated herein by reference to 
          Exhibit 3.2 to the Registration Statement).

    *4.   Rights Agreement, dated February 24, 1999, between the
          Company and Harris Trust and Savings Bank, as Rights Agent.

    *5.   Specimen Certificate representing Common Stock of the Registrant.

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* FILED HEREWITH
 
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