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                                                                       EXHIBIT 5

                                                            March  11, 1994


Union Pacific Corporation
Eighth and Eaton Avenues
Bethlehem, PA  18018

                   RE:    UNION PACIFIC CORPORATION $1,000,000,000 AGGREGATE
                          PRINCIPAL AMOUNT OF DEBT SECURITIES, PREFERRED STOCK,
                          COMMON STOCK AND WARRANTS TO PURCHASE DEBT SECURITIES
                          AND PREFERRED STOCK

Dear Sirs:

         I am Assistant General Counsel of Union Pacific Corporation, a Utah
corporation (the "Company"), and am rendering this opinion in connection with
the Company's Registration Statement on Form S-3 (the "Registration Statement")
being filed today with the Securities and Exchange Commission under the
Securities Act of 1933, as amended (the "Act"), with respect the Company's debt
securities (the "Debt Securities"), preferred stock, with no par value (the
"Preferred Stock"), common stock, par value $2.50 per share (the "Common
Stock") and Warrants to purchase Debt Securities and Preferred Stock (the
"Warrants") (the Debt Securities, Preferred Stock, Common Stock and Warrants
are collectively referred to as the "Offered Securities"), for issuance from
time to time pursuant to Rule 415 under the Act.

         I have examined the Indenture, dated as of March 1, 1994, between the
Company and Citibank, N.A., as Trustee (the "Indenture"), pursuant to which the
Debt Securities will be issued, and I have examined such other documents and
made such other investigations as I have deemed necessary or advisable for
purposes of this opinion.  Based thereon, I am of the opinion that:

         1.  The Company is a corporation duly organized and validly existing
under the laws of the State of Utah.
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         2.  The execution and delivery of the Indenture by the Company and the
issuance and sale of the Offered Securities have been validly authorized by all
necessary corporate action by the Company.

         3.  When (i) the Registration Statement shall have become effective
under the Act, (ii) the securities or Blue Sky laws of certain states shall
have been complied with, and (iii) the Debt Securities shall have been duly
executed, authenticated and delivered against payment therefor or issued upon
conversion or exchange of Debt Securities or Preferred Stock which, by their
respective terms, are convertible into or exchangeable for Debt Securities or
upon exercise of Warrants and the Company shall have received any additional
consideration which is payable upon such conversion, exchange or exercise, the
Debt Securities shall constitute binding obligations of the Company enforceable
in accordance with their terms, except as enforceability may be limited by
bankruptcy, insolvency, reorganization or other laws relating to or affecting
creditors' rights generally and subject to general principles of equity.

         4.  When (i) the Registration Statement shall have become effective
under the Act, (ii) the securities or Blue Sky laws of certain states shall
have been complied with and (iii) the Preferred Stock shall have been sold as
contemplated by the Registration Statement and the Company shall have received
consideration therefor or the Preferred Stock shall have been issued upon
conversion or exchange of Debt Securities which, by their terms, are
convertible into or exchangeable for shares of Preferred Stock or upon exercise
of Warrants and the Company shall have received any additional consideration
which is payable upon such conversion, exchange or exercise, the Preferred
Stock will be validly issued, fully paid and non-assessable.

         5.  When (i) the Registration Statement shall have become effective
under the Act, (ii) the securities or Blue Sky laws of certain states shall
have been complied with, and (iii) the Common Stock shall have been issued upon
conversion or exchange of Debt Securities or Preferred Stock which, by their
respective terms, are convertible into or exchangeable for shares of Common
Stock and the Company shall have received any additional consideration which is
payable upon such conversion or exchange, the Common Stock shall be validly
issued, fully paid and non-assessable.

         6.  When (i) the Registration Statement shall have become effective
under the Act, (ii) the securities or Blue Sky laws of certain states shall
have been complied with, and (iii) a warrant agreement or agreements shall have
been executed and delivered by the Company and a warrant agent, and (iv) the
Warrants shall have





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been duly executed and delivered against payment therefor, the Warrants shall
be legally issued.

         I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.  I also consent to the use of my name under the caption
"Legal Opinions" in the Prospectus contained in the Registration Statement.

                                                       Very truly yours,

                                                       /s/ Richard J. Ressler


RJR/JEJ:nr
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