Document:

<PAGE>   1

                                                                   EXHIBIT 10(a)

                                33,000,000 SHARES

                          THE WILLIAMS COMPANIES, INC.

                                  COMMON STOCK

                             UNDERWRITING AGREEMENT

                                                  January 16, 2001

LEHMAN BROTHERS INC.
MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED
CREDIT SUISSE FIRST BOSTON CORPORATION
As Representatives of the several
  Underwriters named in Schedule 1,
c/o Lehman Brothers Inc.
Three World Financial Center
New York, New York 10285

Dear Sirs:

         The Williams Companies, Inc., a Delaware corporation (the "COMPANY"),
proposes to sell 33,000,000 shares (the "FIRM STOCK") of the Company's Common
Stock, par value $1.00 per share (the "COMMON STOCK") to the several
Underwriters (the "UNDERWRITERS") named in Schedule 1 hereto, subject to the
conditions hereinafter stated. Lehman Brothers Inc., Merrill Lynch, Pierce,
Fenner & Smith Incorporated and Credit Suisse First Boston Corporation shall act
as representatives (the "REPRESENTATIVES") of the several Underwriters.

         In addition, the Company proposes to grant to the Underwriters an
option to purchase up to an additional 4,950,000 shares of the Common Stock on
the terms and for the purposes set forth in Section 3 (the "OPTION Stock"). The
Firm Stock and the Option Stock, if purchased, are hereinafter collectively
called the "STOCK." This is to confirm the agreement concerning the purchase of
the Stock from the Company by the Underwriters.

         SECTION 1. Representations, Warranties and Agreements of the Company.
The Company represents, warrants and agrees that:

          (a) A registration statement on Form S-3 with respect to debt
securities, preferred and common stock of the Company (collectively, the
"SECURITIES"),

<PAGE>   2

including the Stock, has (i) been prepared by the Company in conformity in all
material respects with the requirements of the Securities Act of 1933, as
amended (the "SECURITIES ACT"), and the rules and regulations (the "RULES AND
REGULATIONS") of the Securities and Exchange Commission (the "COMMISSION")
thereunder, (ii) been filed with the Commission under the Securities Act and
(iii) become effective under the Securities Act. The registration statement
includes a prospectus relating to the Securities. In addition, the Company has
filed, or will file within the applicable time period set forth in the Rules and
Regulations, with the Commission, a prospectus supplement specifically relating
to the Stock pursuant to Rule 424 of the Rules and Regulations. The term
"REGISTRATION STATEMENT" means the registration statement as amended to the date
of this Agreement. The term "BASIC PROSPECTUS" means the prospectus included in
the Registration Statement. The term "PROSPECTUS" means the Basic Prospectus
together with the prospectus supplement (other than a preliminary prospectus
supplement) specifically relating to the Stock, in the form first used to
confirm sales of the Stock. The term "PRELIMINARY PROSPECTUS" means a
preliminary prospectus supplement specifically relating to the Stock, together
with the Basic Prospectus. As used herein, the terms "REGISTRATION STATEMENT",
"BASIC PROSPECTUS", "PROSPECTUS" and "PRELIMINARY PROSPECTUS" shall include, in
each case, the material, if any, incorporated by reference therein; "EFFECTIVE
TIME" means the date and time as of which the Registration Statement, or the
most recent post-effective amendment thereto, was declared effective by the
Commission; "EFFECTIVE DATE" means the date of the Effective Time; and the terms
"SUPPLEMENT", "AMEND" and "AMENDMENT", as used in this Agreement with respect to
the Registration Statement or the Prospectus, shall include all documents
subsequently filed by the Company with the Commission pursuant to the Securities
Exchange Act of 1934, as amended (the "EXCHANGE ACT"), that are deemed to be
incorporated by reference in the Prospectus. If the Company has filed an
abbreviated registration statement to register additional shares of Common Stock
pursuant to Rule 462(b) under the Securities Act (the "RULE 462 REGISTRATION
STATEMENT"), then any reference herein to the term "REGISTRATION STATEMENT"
shall be deemed to include such Rule 462 Registration Statement. To the best of
the Company's knowledge, the Commission has not issued any order preventing or
suspending the use of any Preliminary Prospectus.

          (b) The Registration Statement conforms in all material respects, and
the Prospectus and any further amendments or supplements to the Registration
Statement or the Prospectus will, when they become effective or are filed with
the Commission, as the case may be, conform in all material respects to the
requirements of the Securities Act and the Rules and Regulations and do not and
will not, as of the applicable Effective Date (as to the Registration Statement
and any amendment thereto) and as of the applicable filing date (as to the
Prospectus and any amendment or supplement thereto) contain an untrue statement
of a

                                       2
<PAGE>   3

material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein not misleading; provided that no
representation or warranty is made as to information contained in or omitted
from the Registration Statement or the Prospectus in reliance upon and in
conformity with written information furnished to the Company through the
Representatives by or on behalf of any Underwriter specifically for inclusion
therein.

          (c) The Company and each of its significant subsidiaries (as defined
in Rule 1-02 of Regulation S-X under the Securities Act) (each, a "SIGNIFICANT
SUBSIDIARY" and collectively, "SIGNIFICANT SUBSIDIARIES"), which are listed on
Schedule 2 hereto, have been duly incorporated (in the case of each Significant
Subsidiary which is a corporation) or otherwise validly formed and are validly
existing in good standing under the laws of their respective jurisdictions of
organization, are duly qualified to do business and are in good standing in each
jurisdiction in which their respective ownership or lease of property or the
conduct of their respective businesses requires such qualification, except where
failure to have such qualifications would not, singly or in the aggregate, have
a material adverse effect on the consolidated financial position, results of
operation, business or prospects of the Company and its subsidiaries, taken as a
whole, and have all power and authority necessary to own or hold their
respective properties and to conduct the businesses in which they are engaged.

          (d) The Company has an authorized capitalization as set forth in the
Prospectus and all of the issued shares of capital stock of the Company have
been duly authorized and validly issued, are fully paid and non-assessable and
conform to the description thereof contained in the Prospectus; and all of the
issued shares of capital stock of each Significant Subsidiary (in the case of
each Significant Subsidiary which is a corporation) have been duly authorized
and validly issued and are fully paid and non-assessable and (except for
directors' qualifying shares and as disclosed in the Prospectus) are owned
directly or indirectly by the Company, free and clear of all liens,
encumbrances, equities or claims.

          (e) The shares of the Stock to be issued and sold by the Company to
the Underwriters hereunder have been duly authorized and, when issued and
delivered against payment therefor in accordance with this Agreement, will be
validly issued, fully paid and non-assessable; the issuance of such shares of
Stock is not subject to any preemptive rights, and the preferred stock purchase
rights under the Rights Agreement dated as of February 6, 1996 (the "RIGHTS
AGREEMENT") to which holders of the shares of Stock will be entitled have been
duly authorized and, when issued together with such shares of Stock, will be
validly issued and the Stock will conform in all material respects to the
description thereof contained in the Prospectus.

                                       3
<PAGE>   4

         (f) This Agreement has been duly authorized, executed and delivered by
the Company.

          (g) The execution, delivery and performance of this Agreement by the
Company and the consummation of the transactions contemplated hereby will not
conflict with or result in a breach or violation of any of the terms or
provisions of, or constitute a default under, any indenture, mortgage, deed of
trust, loan agreement or other agreement or instrument to which the Company or
any of its Significant Subsidiaries is a party or by which the Company or any of
its Significant Subsidiaries is bound or to which any of the property or assets
of the Company or any of its Significant Subsidiaries is subject, other than
such conflicts, agreements, breaches, violations or defaults which, singly or in
the aggregate, would not have a material adverse effect on the consolidated
financial position, results of operations, business or prospects of the Company
and its subsidiaries, taken as a whole, nor will such actions result in any
violation of the provisions of the charter or by-laws of the Company or any of
its Significant Subsidiaries or any statute or any order, rule or regulation
known to the Company of any court or governmental agency or body having
jurisdiction over the Company or any of its Significant Subsidiaries or any of
their properties or assets; and except for the registration of the Stock under
the Securities Act and such consents, approvals, authorizations, registrations
or qualifications as may be required under the Exchange Act, the Securities Act,
applicable state securities laws and securities laws of foreign jurisdictions in
connection with the purchase and distribution of the Stock by the Underwriters,
no consent, approval, authorization or order of, or filing or registration with,
any such court or governmental agency or body is required for the execution,
delivery and performance of this Agreement and the consummation of the
transactions contemplated hereby.

          (h) Except as described in the Prospectus and except for the
registration rights granted in connection with the sale of the Company's 7.50%
Debentures due January 15, 2031 and the 6.75% Putable Asset Term Securities
Putable/Callable January 15, 2006, there are no contracts, agreements or
understandings between the Company and any person granting such person the right
to require the Company to file a registration statement under the Securities Act
with respect to any securities of the Company owned or to be owned by such
person or to require the Company to include any securities of the Company in the
securities registered pursuant to the Registration Statement.

          (i) Neither the Company nor any of its Significant Subsidiaries has
sustained, since the respective dates as of which information is given in the
Prospectus, any loss or interference with its business from fire, explosion,
flood or other calamity, whether or not covered by insurance, or from any labor
dispute or court or governmental action, order or decree that has resulted in,
or is reasonably

                                       4
<PAGE>   5

likely to result in, a material adverse change in the consolidated financial
position, results of operations, business or prospects of the Company and its
subsidiaries, taken as a whole, otherwise than as set forth or contemplated in
the Prospectus; and, since such date, there has not been any material change in
the capital stock or long-term debt of the Company or any of its subsidiaries or
any material adverse change, or any development involving a prospective material
adverse change, in or affecting the consolidated financial position, results of
operations, business or prospects of the Company and its subsidiaries, taken as
a whole, otherwise than as set forth or contemplated in the Prospectus.

          (j) The financial statements (including the related notes and
supporting schedules) filed as part of the Registration Statement or included in
the Prospectus present fairly, in all material respects, the financial condition
and results of operations of the entities purported to be shown thereby, at the
dates and for the periods indicated, and have been prepared in conformity with
generally accepted accounting principles applied on a consistent basis
throughout the periods involved, except as may be indicated in the notes
thereto.

          (k) Ernst & Young, who have certified certain financial statements of
the Company, whose report appears, or is incorporated by reference, in the
Prospectus and who have delivered the initial letter referred to in Section 7(f)
hereof, are independent public accountants as required by the Securities Act and
the Rules and Regulations; and Deloitte & Touche, whose report appears, or is
incorporated by reference, in the Prospectus, were independent accountants as
required by the Securities Act and the Rules and Regulations during the periods
covered by the financial statements on which they reported.

          (l) The Company and each of its Significant Subsidiaries have good
title to all real property and good title to all personal property owned by
them, in each case free and clear of all liens, encumbrances and defects, except
such as are described in the Prospectus or such as do not materially affect the
value of such property and do not materially interfere with the conduct of
business of the Company and its subsidiaries, taken as a whole; and all assets
held under lease by the Company and its Significant Subsidiaries are held by
them under valid, subsisting and enforceable leases, with such exceptions as are
not material and do not interfere with the conduct of business of the Company
and its subsidiaries, taken as a whole.

          (m) The Company and each of its Significant Subsidiaries carry, or are
covered by, insurance in such amounts and covering such risks as the Company
believes is adequate for the conduct of their respective businesses and the
value of their respective properties and as the Company believes is customary
for companies engaged in similar businesses in similar industries.

                                       5
<PAGE>   6

          (n) The Company and each of its Significant Subsidiaries own or
possess, or can acquire on reasonable terms, adequate rights to use all material
patents, patent applications, trademarks, service marks, trade names, copyrights
and licenses necessary for the conduct of their respective businesses and have
no reason to believe that the conduct of their respective businesses will
conflict with, and have not received any notice of any claim of conflict with,
any such rights of others which, singly or in the aggregate, in the judgment of
the Company, is reasonably likely to result in any material adverse change in
the consolidated financial position, results of operations, business or
prospects of the Company and its subsidiaries, taken as a whole.

          (o) Except as described in the Prospectus, there are no legal or
governmental proceedings pending to which the Company or any of its Significant
Subsidiaries is a party or of which any property or assets of the Company or any
of its Significant Subsidiaries is the subject which, if determined adversely to
the Company or any of its Significant Subsidiaries, might have a material
adverse effect on the consolidated financial position, results of operations,
business or prospects of the Company and its subsidiaries, taken as a whole; and
to the best of the Company's knowledge, no such proceedings are threatened or
contemplated by governmental authorities or threatened by others.

          (p) There are no contracts or other documents which are required to be
described in the Prospectus or filed as exhibits to the Registration Statement
by the Securities Act or by the Rules and Regulations which have not been
described in the Prospectus or filed as exhibits to the Registration Statement.

          (q) No business or related party transaction exists which is required
by Item 404 of Regulation S-K to be described in the Prospectus which is not so
described.

          (r) The Company is in compliance in all material respects with all
presently applicable provisions of the Employee Retirement Income Security Act
of 1974, as amended, including the regulations and published interpretations
thereunder ("ERISA"); no "REPORTABLE EVENT" (as defined in ERISA) has occurred
with respect to any "PENSION PLAN" (as defined in ERISA) for which the Company
would have any liability; the Company has not incurred and does not expect to
incur liability under (i) Title IV of ERISA with respect to termination of, or
withdrawal from, any "PENSION PLAN" or (ii) Sections 412 or 4971 of the Internal
Revenue Code of 1986, as amended, including the regulations and published
interpretations thereunder (the "CODE"); and each "PENSION PLAN" for which the
Company would have any liability that is intended to be qualified under Section
401(a) of the Code is so qualified in all material respects and nothing has

                                       6
<PAGE>   7

occurred, whether by action or by failure to act, which would cause the loss of
such qualification.

          (s) The Company has filed all material federal, state and local income
and franchise tax returns required to be filed through the date hereof and has
paid all taxes due thereon, other than those filings or payments being contested
in good faith, and the Company has not received notice that any tax deficiency
has been determined adversely to the Company or any of its Significant
Subsidiaries which has had or is reasonably likely to have a material adverse
effect on the consolidated financial position, results of operations, business
or prospects of the Company and its subsidiaries, taken as a whole.

          (t) Since the date as of which information is given in the Prospectus
through the date hereof, and except as may otherwise be disclosed in the
Prospectus or with respect to the subsequent issuance of shares of Common Stock,
if any, pursuant to employee or director benefit plans, the Company has not (i)
issued or granted any securities, (ii) incurred any liability or obligation,
direct or contingent, other than liabilities and obligations which were incurred
in the ordinary course of business, (iii) entered into any transaction not in
the ordinary course of business, except, in case of (ii) and (iii), for such
liabilities, obligations or transactions that have not had or are not reasonably
expected to have, a material adverse effect on the consolidated financial
conditions, results of operations, business or prospects of the Company and its
subsidiaries, taken as a whole or (iv) declared or paid any dividend on its
capital stock.

          (u) The Company (i) makes and keeps accurate books and records and
(ii) maintains internal accounting controls which provide reasonable assurance
that (A) transactions are executed in accordance with management's
authorization, (B) transactions are recorded as necessary to permit preparation
of its financial statements and to maintain accountability for its assets, (C)
access to its assets is permitted only in accordance with management's
authorization and (D) the reported accountability for its assets is compared
with existing assets at reasonable intervals.

          (v) Neither the Company nor any of its Significant Subsidiaries (i) is
in violation of its charter or by-laws, (ii) is in default in any material
respect, and no event has occurred which, with notice or lapse of time or both,
would constitute such a default, in the due performance or observance of any
term, covenant or condition contained in any material indenture, mortgage, deed
of trust, loan agreement or other agreement or instrument to which it is a party
or by which it is bound or to which any of its properties or assets is subject
or (iii) is in violation in any material respect of any law, ordinance,
governmental rule, regulation or court decree to which it or its property or
assets may be subject or has failed to obtain any material license, permit,
certificate, franchise or other governmental

                                       7
<PAGE>   8

authorization or permit necessary to the ownership of its property or to the
conduct of its business except, in case of (ii) and (iii), for such defaults,
violations, or failures to obtain such authorizations or permits that have not
had or are not reasonably expected to have, a material adverse effect on the
consolidated financial condition, results of operations, business or prospects
of the Company and its subsidiaries, taken as a whole.

          (w) There has been no storage, disposal, generation, manufacture,
refinement, transportation, handling or treatment of toxic wastes, medical
wastes, hazardous wastes or hazardous substances by the Company or any of its
Significant Subsidiaries (or, to the knowledge of the Company, any of their
predecessors in interest) at, upon or from any of the property now or previously
owned or leased by the Company or its Significant Subsidiaries in violation of
any applicable law, ordinance, rule, regulation, order, judgment, decree or
permit or which would require remedial action under any applicable law,
ordinance, rule, regulation, order, judgment, decree or permit, except for any
violation or remedial action which would not have, or could not be reasonably
likely to have, singularly or in the aggregate with all such violations and
remedial actions, a material adverse effect on the consolidated financial
position, results of operations, business or prospects of the Company and its
subsidiaries, taken as a whole; there has been no material spill, discharge,
leak, emission, injection, escape, dumping or release of any kind onto such
property or into the environment surrounding such property of any toxic wastes,
medical wastes, solid wastes, hazardous wastes or hazardous substances due to or
caused by the Company or any of its Significant Subsidiaries or with respect to
which the Company or any of its Significant Subsidiaries have knowledge, except
for any such spill, discharge, leak, emission, injection, escape, dumping or
release which would not have or would not be reasonably likely to have,
singularly or in the aggregate with all such spills, discharges, leaks,
emissions, injections, escapes, dumpings and releases, a material adverse effect
on the consolidated financial position, results of operations, business or
prospects of the Company and its subsidiaries, taken as a whole; and the terms
"HAZARDOUS WASTES", "TOXIC WASTES", "HAZARDOUS SUBSTANCES" and "MEDICAL WASTES"
shall have the meanings specified in any applicable local, state, federal and
foreign laws or regulations with respect to environmental protection.

          (x) The Company is not, and, after giving effect to the offering
contemplated hereby and the application of the net proceeds therefrom as
described in the Prospectus, will not be, an "investment company" as defined in
the Investment Company Act of 1940, as amended.

         SECTION 2. Purchase of the Stock by the Underwriters. On the basis of
the representations and warranties contained in, and subject to the terms and

                                       8
<PAGE>   9

conditions of, this Agreement, the Company agrees to sell the Firm Stock to the
several Underwriters and each of the Underwriters, severally and not jointly,
agrees to purchase the number of shares of the Firm Stock set forth opposite
that Underwriter's name in Schedule 1 hereto. The respective purchase
obligations of the Underwriters with respect to the Firm Stock shall be rounded
among the Underwriters to avoid fractional shares, as the Representatives may
determine.

         In addition, the Company grants to the Underwriters an option to
purchase up to 4,500,000 shares of Option Stock. Such option is granted for the
purpose of covering over-allotments in the sale of Firm Stock and is exercisable
as provided in Section 4 hereof. Shares of Option Stock shall be purchased
severally for the account of the Underwriters in proportion to the number of
shares of Firm Stock set forth opposite the name of such Underwriter in Schedule
1 hereto. The respective purchase obligations of each Underwriter with respect
to the Option Stock shall be adjusted by the Representatives so that no
Underwriter shall be obligated to purchase Option Stock other than in 100 share
amounts.

         The price of both the Firm Stock and any Option Stock to be paid by the
Underwriters shall be $35.135 per share.

         The Company shall not be obligated to deliver any of the Stock to be
delivered on any Delivery Date (as hereinafter defined), except upon payment for
all the Stock to be purchased on such Delivery Date as provided herein.

         SECTION 3. Offering of Stock by the Underwriters.

         Upon authorization by the Representatives of the release of the Firm
Stock, the several Underwriters propose to offer the Firm Stock for sale upon
the terms and conditions set forth in the Prospectus.

         SECTION 4. Delivery of and Payment for the Stock. Delivery of and
payment for the Firm Stock shall be made at the offices of Davis Polk &
Wardwell, 450 Lexington Avenue, New York, New York 10017, at 10:00 A.M., New
York City time, on January 22, 2001 or at such other date or place as shall be
determined by agreement between the Representatives and the Company. This date
and time are sometimes referred to as the "FIRST DELIVERY DATE." On the First
Delivery Date, the Company shall deliver or cause to be delivered certificates
representing the Firm Stock to the Representatives for the account of each
Underwriter against payment to or upon the order of the Company of the purchase
price by wire transfer in immediately available funds. Time shall be of the
essence, and delivery at the time and place specified pursuant to this Agreement
is a further condition of the obligation of each Underwriter hereunder. Upon
delivery, the Firm Stock shall be registered in such names and in such
denominations as the Representatives shall request in writing not less than two

                                       9
<PAGE>   10

full business days prior to the First Delivery Date. For the purpose of
expediting the checking and packaging of the certificates for the Firm Stock,
the Company shall make the certificates representing the Firm Stock available
for inspection by the Representatives in New York, New York, not later than 2:00
P.M., New York City time, on the business day prior to the First Delivery Date.

         The option granted in Section 2 will expire 30 days after the date of
this Agreement and may be exercised in whole or in part from time to time by
written notice being given to the Company by the Representatives. Such notice
shall set forth the aggregate number of shares of Option Stock as to which the
option is being exercised, the names in which the shares of Option Stock are to
be registered, the denominations in which the shares of Option Stock are to be
issued and the date and time, as determined by the Representatives, when the
shares of Option Stock are to be delivered; provided, however, that this date
and time shall not be earlier than the First Delivery Date nor earlier than the
second business day after the date on which the option shall have been exercised
nor later than the fifth business day after the date on which the option shall
have been exercised. The date and time the shares of Option Stock are delivered
are sometimes referred to as a "SECOND DELIVERY DATE" and the First Delivery
Date and any Second Delivery Date are sometimes each referred to as a "DELIVERY
DATE".

         Delivery of and payment for the Option Stock shall be made at the place
specified in the first sentence of the first paragraph of this Section 4 (or at
such other place as shall be determined by agreement between the Representatives
and the Company) at 10:00 A.M., New York City time, on such Second Delivery
Date. On such Second Delivery Date, the Company shall deliver or cause to be
delivered the certificates representing the Option Stock to the Representatives
for the account of each Underwriter against payment to or upon the order of the
Company of the purchase price by wire transfer in immediately available funds.
Time shall be of the essence, and delivery at the time and place specified
pursuant to this Agreement is a further condition of the obligation of each
Underwriter hereunder. Upon delivery, the Option Stock shall be registered in
such names and in such denominations as the Representatives shall request in the
aforesaid written notice. For the purpose of expediting the checking and
packaging of the certificates for the Option Stock, the Company shall make the
certificates representing the Option Stock available for inspection by the
Representatives in New York, New York, not later than 2:00 P.M., New York City
time, on the business day prior to such Second Delivery Date.

         SECTION 5. Further Agreements of the Company. The Company agrees:

          (a) To prepare the Prospectus in a form approved by the
Representatives and to file such Prospectus pursuant to Rule 424(b) under the
Securities Act not later than Commission's close of business on the second
business day following

                                       10
<PAGE>   11

the execution and delivery of this Agreement; to make no further amendment or
any supplement to the Registration Statement or to the Prospectus except as
permitted herein; to advise the Representatives, promptly after it receives
notice thereof, of the time when any amendment to the Registration Statement has
been filed or becomes effective or any supplement to the Prospectus or any
amended Prospectus has been filed and to furnish the Representatives with copies
thereof; to advise the Representatives, promptly after it receives notice
thereof, of the issuance by the Commission of any stop order or of any order
preventing or suspending the use of any Preliminary Prospectus or the
Prospectus, of the suspension of the qualification of the Stock for offering or
sale in any jurisdiction, of the initiation or threatening of any proceeding for
any such purpose, or of any request by the Commission for the amending or
supplementing of the Registration Statement or the Prospectus or for additional
information; and, in the event of the issuance of any stop order or of any order
preventing or suspending the use of any Preliminary Prospectus or the Prospectus
or suspending any such qualification, to use promptly its reasonable best
efforts to obtain its withdrawal;

          (b) To furnish promptly to each of the Representatives and to counsel
for the Underwriters a conformed copy of the Registration Statement as
originally filed with the Commission, and each amendment thereto filed with the
Commission, including all consents and exhibits filed therewith;

          (c) To deliver promptly to the Representatives such number of the
following documents as the Representatives shall reasonably request: (i)
conformed copies of the Registration Statement as originally filed with the
Commission and each amendment thereto (in each case excluding exhibits) and (ii)
each Preliminary Prospectus, the Prospectus and any amended or supplemented
Prospectus; and, if the delivery of a prospectus is required at any time after
the Effective Time in connection with the offering or sale of the Stock or any
other securities relating thereto and if at such time any events shall have
occurred as a result of which the Prospectus as then amended or supplemented
would include an untrue statement of a material fact or omit to state any
material fact necessary in order to make the statements therein, in the light of
the circumstances under which they were made when such Prospectus is delivered,
not misleading, or, if for any other reason it shall be necessary to amend or
supplement the Prospectus in order to comply with the Securities Act, to notify
the Representatives and, upon their request, to prepare and furnish without
charge to each Underwriter and to any dealer in securities as many copies as the
Representatives may from time to time reasonably request of an amended or
supplemented Prospectus which will correct such statement or omission or effect
such compliance.

          (d) To file promptly with the Commission any amendment to the
Registration Statement or the Prospectus or any supplement to the Prospectus
that

                                       11
<PAGE>   12

may, in the judgment of the Company or the Representatives, be required by the
Securities Act or requested by the Commission;

          (e) Prior to filing with the Commission any amendment to the
Registration Statement or supplement to the Prospectus or any Prospectus
pursuant to Rule 424 of the Rules and Regulations, to furnish a copy thereof to
the Representatives and counsel for the Underwriters and obtain the consent of
the Representatives to the filing, which consent shall not be unreasonably
withheld;

          (f) As soon as practicable after the date of this Agreement, to make
generally available to the Company's security holders and to deliver to the
Representatives an earnings statement of the Company and its subsidiaries (which
need not be audited) complying with Section 11(a) of the Securities Act and the
Rules and Regulations (including, at the option of the Company, Rule 158);

          (g) Promptly from time to time to take such action, with the
cooperation of the Representatives, as the Representatives may reasonably
request to qualify the Stock for offering and sale under the securities laws of
such jurisdictions as the Representatives may reasonably request and to comply
with such laws so as to permit the continuance of sales and dealings therein in
such jurisdictions for as long as may be reasonably necessary to complete the
distribution of the Stock; provided that in connection therewith the Company
shall not be required to qualify as a foreign corporation or to file a general
consent to service of process in any jurisdiction;

          (h) For a period of 90 days from the date of the Prospectus, not to,
directly or indirectly, (1) offer for sale, sell, pledge or otherwise dispose of
(or enter into any transaction or device which is designed to, or could be
expected to, result in the disposition by any person at any time in the future
of) any shares of Common Stock or securities convertible into or exchangeable
for Common Stock (other than (a) the Stock, (b) shares of Common Stock issued
pursuant to employee benefit plans, qualified stock option plans or other
employee compensation plans existing on the date hereof or pursuant to currently
outstanding options, warrants or rights and (c) shares of Common Stock used as
consideration for acquisitions or issued in connection with strategic alliances,
provided that the recipient of any such shares of Common Stock agrees to be
bound by the transfer restrictions set forth herein for the unexpired remaining
term thereof), or sell or grant options, rights or warrants with respect to any
shares of Common Stock or securities convertible into or exchangeable for Common
Stock (other than the grant of options pursuant to option plans existing on the
date hereof), or (2) enter into any swap or other derivatives transaction that
transfers to another, in whole or in part, any of the economic benefits or risks
of ownership of such shares of Common Stock, whether any such transaction
described in clause (1) or (2) above is to be settled by delivery of Common
Stock or other securities,

                                       12
<PAGE>   13

in cash or otherwise, in each case without the prior written consent of Lehman
Brothers Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated on behalf
of the Underwriters; and to cause each executive officer and director of the
Company to furnish to the Representatives, prior to the First Delivery Date, a
letter or letters, substantially in the form of Exhibit A hereto, pursuant to
which each such person shall agree not to, directly or indirectly, (1) offer for
sale, sell, pledge or otherwise dispose of (or enter into any transaction or
device which is designed to, or could be expected to, result in the disposition
by any person at any time in the future of) any shares of Common Stock or
securities convertible into or exchangeable for Common Stock or (2) enter into
any swap or other derivatives transaction that transfers to another, in whole or
in part, any of the economic benefits or risks of ownership of such shares of
Common Stock, whether any such transaction described in clause (1) or (2) above
is to be settled by delivery of Common Stock or other securities, in cash or
otherwise, in each case for a period of 90 days from the date of the Prospectus,
without the prior written consent of Lehman Brothers Inc. and Merrill Lynch,
Pierce, Fenner & Smith Incorporated on behalf of the Underwriters;

         (i) To apply for the listing of the Stock on the New York Stock
Exchange, and to use its reasonable best efforts to complete that listing,
subject only to official notice of issuance, prior to the First Delivery Date;

         (j) To apply the net proceeds from the sale of the Stock as set forth
in the Prospectus; and

         (k) To take such steps as shall be necessary to ensure that neither the
Company nor any subsidiary shall become an "investment company" as defined in
the Investment Company Act of 1940, as amended.

         SECTION 6. Expenses. The Company agrees to pay (a) the costs incident
to the authorization, issuance, sale and delivery of the Stock and any taxes
payable in that connection; (b) the costs incident to the preparation, printing
and filing under the Securities Act of the Registration Statement and any
amendments and exhibits thereto; (c) the costs of distributing the Registration
Statement as originally filed and each amendment thereto and any post-effective
amendments thereof (including, in each case, exhibits), any Preliminary
Prospectus, the Prospectus and any amendment or supplement to the Prospectus,
all as provided in this Agreement; (d) the costs of producing and distributing
this Agreement and any other related documents in connection with the offering,
purchase, sale and delivery of the Stock; (e) any filing fees incident to
securing the review by the National Association of Securities Dealers, Inc. of
the terms of sale of the Stock; (f) any applicable listing or other fees; (g)
the fees and expenses (not in excess, in the aggregate, of $10,000) of
qualifying the Stock under the securities laws of the several jurisdictions as
provided in Section 5(g) and of preparing, printing and

                                       13
<PAGE>   14

distributing a Blue Sky Memorandum (including related fees and expenses of
counsel to the Underwriters); (h) the costs and expenses of the Company relating
to investor presentations on any "ROAD SHOW" undertaken in connection with the
marketing of the offering of the Stock, including, without limitation, expenses
associated with the production of road show slides and graphics, fees and
expenses of any consultants engaged in connection with the road show
presentations with the prior approval of the Company, travel and lodging
expenses of the representatives and officers of the Company and any such
consultants, and the cost of any aircraft chartered (with the approval of the
Company) in connection with the road show and (i) all other costs and expenses
incident to the performance of the obligations of the Company under this
Agreement; provided that, except as provided in this Section 6 and in Section
11, the Underwriters shall pay their own costs and expenses, including the costs
and expenses of their counsel, any transfer taxes on the Stock which they may
sell and the expenses of advertising any offering of the Stock made by the
Underwriters.

         SECTION 7. Conditions of Underwriters' Obligations. The respective
obligations of the Underwriters hereunder are subject to the accuracy, when made
and on each Delivery Date, of the representations and warranties of the Company
contained herein, to the performance by the Company of its obligations
hereunder, and to each of the following additional terms and conditions:

          (a) The Prospectus shall have been timely filed with the Commission in
accordance with Section 5(a); no stop order suspending the effectiveness of the
Registration Statement or any part thereof shall have been issued and no
proceeding for that purpose shall have been initiated or threatened by the
Commission; and any request of the Commission for inclusion of additional
information in the Registration Statement or the Prospectus or otherwise shall
have been complied with.

          (b) All corporate proceedings and other legal matters incident to the
authorization of this Agreement, the Stock, the Registration Statement and the
Prospectus, and all other legal matters relating to this Agreement and the
transactions contemplated hereby shall be reasonably satisfactory in all
material respects to counsel for the Underwriters, and the Company shall have
furnished to such counsel all documents and information that they may reasonably
request to enable them to pass upon such matters.

          (c) William von Glahn, Senior Vice President and General Counsel of
the Company, shall have furnished to the Representatives his written opinion,
addressed to the Underwriters and dated such Delivery Date, in form and
substance reasonably satisfactory to the Representatives, to the effect that:

                                       14
<PAGE>   15

                  (i) The Company and each of its Significant Subsidiaries have
         been duly incorporated (in the case of each Significant Subsidiary that
         is a corporation) or otherwise validly formed and are validly existing
         in good standing under the laws of their respective jurisdictions of
         organization, are duly qualified to do business and are in good
         standing in each jurisdiction in which their respective ownership or
         lease of property or the conduct of their respective businesses
         requires such qualification, except to the extent such failure to be
         qualified or in good standing would not have a material adverse effect
         on the consolidated financial position, results of operations, business
         or prospects of the Company and its subsidiaries, taken as a whole, and
         have all power and authority necessary to own or hold their respective
         properties and conduct the businesses in which they are engaged as
         described in or contemplated by the Registration Statement; and all of
         the issued shares of capital stock of each Significant Subsidiary (in
         the case of each Significant Subsidiary that is a corporation) have
         been duly and validly authorized and issued and are fully paid,
         non-assessable and (except for directors' qualifying shares and as
         disclosed in the Prospectus) are owned directly or indirectly by the
         Company, free and clear of all liens, encumbrances, equities or claims;

                 (ii) To the best of such counsel's knowledge and other than as
         set forth in the Prospectus, there are no legal or governmental
         proceedings pending to which the Company or any of its Significant
         Subsidiaries is a party or of which any property or assets of the
         Company or any of its Significant Subsidiaries is the subject which, if
         determined adversely to the Company or any of its Significant
         Subsidiaries, could reasonably be expected to have a material adverse
         effect on the consolidated financial position, results of operations,
         business or prospects of the Company and its subsidiaries, taken as a
         whole; and, to the best of such counsel's knowledge, no such
         proceedings are threatened or pending by governmental authorities or
         threatened by others;

                (iii) Except as described in the Prospectus and except for the
         registration rights granted in connection with the sale of the
         Company's 7.50% Debentures due January 15, 2031 and the 6.75% Putable
         Asset Term Securities Putable/Callable January 15, 2006, to the best of
         such counsel's knowledge, there are no contracts, agreements or
         understandings between the Company and any person granting such person
         the right to require the Company to file a registration statement under
         the Securities Act with respect to any securities of the Company owned
         or to be owned by such person or to require the Company to include such
         securities in the securities registered pursuant to the Registration
         Statement;

                                       15
<PAGE>   16

                 (iv) The Company is in compliance in all material respects with
         all presently applicable provisions of ERISA; no "reportable event" (as
         defined in ERISA) has occurred with respect to any "PENSION PLAN" (as
         defined in ERISA) for which the Company would have any liability; the
         Company has not incurred and does not expect to incur liability under
         (i) Title IV of ERISA with respect to termination of, or withdrawal
         from, any "PENSION PLAN" or (ii) Sections 412 or 4971 of the Code; and
         each "PENSION PLAN" for which the Company would have any liability that
         is intended to be qualified under Section 401(a) of the Code is so
         qualified in all material respects and nothing has occurred, whether by
         action or by failure to act, which would cause the loss of such
         qualification;

                  (v) There has been no storage, disposal, generation,
         manufacture, refinement, transportation, handling or treatment of toxic
         wastes, medical wastes, hazardous wastes or hazardous substances by the
         Company or any of its Significant Subsidiaries (or, to the knowledge of
         such counsel, any of their predecessors in interest) at, upon or from
         any of the property now or previously owned or leased (but not
         including property on which the Company had or has easements or similar
         rights) by the Company or its Significant Subsidiaries in violation of
         any applicable law, ordinance, rule, regulation, order, judgment,
         decree or permit or which would require remedial action under any
         applicable law, ordinance, rule, regulation, order, judgment, decree or
         permit, except for any violation or remedial action which would not
         have, or could not be reasonably likely to have, singularly or in the
         aggregate with all such violations and remedial actions, a material
         adverse effect on the consolidated financial position, results of
         operations, business or prospects of the Company and its subsidiaries,
         taken as a whole; there has been no material spill, discharge, leak,
         emission, injection, escape, dumping or release of any kind onto such
         property or into the environment surrounding such property of any toxic
         wastes, medical wastes, solid wastes, hazardous wastes or hazardous
         substances due to or caused by the Company or any of its Significant
         Subsidiaries or with respect to which the Company or any of its
         Significant Subsidiaries have knowledge, except for any such spill,
         discharge, leak, emission, injection, escape, dumping or release which
         would not have or would not be reasonably likely to have, singularly or
         in the aggregate with all such spills, discharges, leaks, emissions,
         injections, escapes, dumpings and releases, a material adverse effect
         on the consolidated financial position, results of operations, business
         or prospects of the Company and its subsidiaries, taken as a whole;

                 (vi) The Company has an authorized capitalization as set forth
         in the Prospectus under the "Actual" column under the caption

                                       16
<PAGE>   17

         "Capitalization," and all of the issued shares of capital stock of the
         Company have been duly authorized and validly issued, are fully paid
         and non-assessable and conform in all material respects to the
         description thereof contained in the Prospectus;

                (vii) The shares of the Stock being delivered on such Delivery
         Date to the Underwriters hereunder have been duly authorized and, when
         issued and delivered against payment therefor will be validly issued,
         fully paid and non-assessable, the issuance of such shares of Stock is
         not subject to any preemptive rights, and the preferred stock purchase
         rights under the Rights Agreement to which holders of the shares of
         Stock will be entitled have been duly authorized and, when issued
         together with such shares of Stock, will be validly issued;

               (viii) Except as described in the Prospectus, there are no
         preemptive or other rights to subscribe for or to purchase, nor any
         restriction upon the voting or transfer of, any shares of the Stock
         pursuant to the Company's charter or by-laws or any agreement or other
         instrument to which the Company is a party;

                 (ix) Neither the Company nor any of its Significant
         Subsidiaries (i) is in violation of its charter or by-laws, (ii) is in
         default in any material respect, and no event has occurred which, with
         notice or lapse of time or both, would constitute such a default, in
         the due performance or observance of any term, covenant or condition
         contained in any material indenture, mortgage, deed of trust, loan
         agreement or other agreement or instrument to which it is a party or by
         which it is bound or to which any of its properties or assets is
         subject or (iii) is in violation in any material respect of any law,
         ordinance, governmental rule, regulation or court decree to which it or
         its property or assets may be subject or has failed to obtain any
         material license, permit, certificate, franchise or other governmental
         authorization or permit necessary to the ownership of its property or
         to the conduct of its business except, in case of (ii) and (iii), for
         such defaults, violations, or failures to obtain such authorizations or
         permits that have not had or are not reasonably expected to have, a
         material adverse effect on the consolidated financial condition,
         results of operations, business or prospects of the Company and its
         subsidiaries, taken as a whole;

                  (x) The execution, delivery and performance of this Agreement
         by the Company and the consummation of the transactions contemplated
         hereby will not conflict with or result in a breach or violation of any
         of the terms or provisions of, or constitute a default under, any
         indenture, mortgage, deed of trust, loan agreement or other agreement
         or instrument

                                       17
<PAGE>   18

         to which the Company or any of its Significant Subsidiaries is a party
         or by which the Company or any of its Significant Subsidiaries is bound
         or to which any of the property or assets of the Company or any of its
         Significant Subsidiaries is subject, other than such conflicts,
         agreements, breaches, violations or defaults which, singly or in the
         aggregate, would not have a material adverse effect on the consolidated
         financial position, results of operations, business or prospects of the
         Company and its subsidiaries, taken as a whole, nor will such actions
         result in any violation of the provisions of the charter or by-laws of
         the Company or any of its Significant Subsidiaries or any statute or
         any order, rule or regulation known to the Company of any court or
         governmental agency or body having jurisdiction over the Company or any
         of its Significant Subsidiaries or any of their properties or assets;
         and except for the registration of the Stock under the Securities Act
         and such consents, approvals, authorizations, registrations or
         qualifications as may be required under the Exchange Act, the
         Securities Act, applicable state securities laws and securities laws of
         foreign jurisdictions in connection with the purchase and distribution
         of the Stock by the Underwriters, no consent, approval, authorization
         or order of, or filing or registration with, any such court or
         governmental agency or body is required for the execution, delivery and
         performance of this Agreement and the consummation of the transactions
         contemplated hereby;

                 (xi) The Company is not, and after giving effect to the
         offering of the Stock and the application of the net proceeds therefrom
         will not be, an "investment company" as defined in the Investment
         Company Act of 1940, as amended;

                (xii) The statements in (1) the Prospectus under the captions
         "Description of Common Stock", "Description of Preferred Stock" and
         "Plan of Distribution" in the Basic Prospectus and under the caption
         "Underwriting" in the Prospectus, (2) in the Registration Statement
         under Item 15 and (3) in the Company's most recent Annual Report on
         Form 10-K or Form 10/K-A, as the case may be, and in the Company's most
         recent Quarterly Report on Form 10-Q under "Business" and "Legal
         Proceedings", in each case insofar as such statements constitute
         summaries of the legal matters, documents or proceedings referred to
         therein, fairly present the information called for with respect to such
         legal matters, documents or proceedings and fairly summarize the
         matters referred to therein;

               (xiii) After due inquiry, such counsel does not know of any legal
         or governmental proceeding pending or threatened to which the Company
         or any of its subsidiaries is subject which is required to be described
         or of any

                                       18
<PAGE>   19

         contract or other document which is required to be described in the
         Registration Statement or the Prospectus or to be filed as an exhibit
         to the Registration Statement which is not described or filed as
         required; and

                (xiv) Such counsel (a) is of the opinion that (except as to the
         financial statements included therein, as to which such counsel need
         not express any opinion) each document, if any, filed pursuant to the
         Exchange Act and incorporated by reference into the Registration
         Statement and the Prospectus complied when so filed as to form in all
         material respects with the Exchange Act and the rules and regulations
         of the Commission thereunder, (b) is of the opinion that the
         Registration Statement and the Prospectus, as amended or supplemented,
         if applicable (except as to the financial statements included therein,
         as to which such counsel need not express any opinion), comply as to
         form in all material respects with the Securities Act and the Rules and
         Regulations, (c) believes that (except as to the financial statements
         included therein, as to which such counsel need not express any
         belief), each part of the Registration Statement when such part became
         effective or was incorporated by reference into the Registration
         Statement did not contain, and as of the date of such opinion, does not
         contain, any untrue statement of a material fact or omit to state a
         material fact required to be stated therein or to make the statements
         therein not misleading, and (d) believes that (except as to the
         financial statements included therein, as to which such counsel need
         not express any belief) the Registration Statement and the Prospectus,
         as amended or supplemented, if applicable, do not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         in order to make the statements therein, in light of the circumstances
         under which they were made, not misleading.

         In rendering such opinion, such counsel may state that his opinion is
limited to matters governed by the Federal laws of the United States of America,
the laws of the State of New York and the State of Oklahoma and the General
Corporation Law of the State of Delaware.

          (d) The Representatives shall have received from Davis Polk &
Wardwell, counsel for the Underwriters, such opinion or opinions, dated such
Delivery Date, with respect to the issuance and sale of the Stock, the
Registration Statement, the Prospectus and other related matters as the
Representatives may reasonably require, and the Company shall have furnished to
such counsel such documents as they reasonably request for the purpose of
enabling them to pass upon such matters.

          (e) At the time of execution of this Agreement, the Representatives
shall have received from Ernst & Young a letter, in form and substance
satisfactory to

                                       19
<PAGE>   20

the Representatives, addressed to the Underwriters and dated the date hereof (i)
confirming that they are independent public accountants within the meaning of
the Securities Act and are in compliance with the applicable requirements
relating to the qualification of accountants under Rule 2-01 of Regulation S-X
of the Commission and (ii) stating, as of the date hereof (or, with respect to
matters involving changes or developments since the respective dates as of which
specified financial information is given in the Prospectus, as of a date not
more than five days prior to the date hereof), the conclusions and findings of
such firm with respect to the financial information and other matters ordinarily
covered by accountants' "COMFORT LETTERS" to underwriters in connection with
registered public offerings.

          (f) With respect to the letter of Ernst & Young referred to in the
preceding paragraph and delivered to the Representatives concurrently with the
execution of this Agreement (the "INITIAL LETTER"), the Company shall have
furnished to the Representatives a letter (the "BRING-DOWN LETTER") of such
accountants, addressed to the Underwriters and dated such Delivery Date (i)
confirming that they are independent public accountants within the meaning of
the Securities Act and are in compliance with the applicable requirements
relating to the qualification of accountants under Rule 2-01 of Regulation S-X
of the Commission, (ii) stating, as of the date of the bring-down letter (or,
with respect to matters involving changes or developments since the respective
dates as of which specified financial information is given in the Prospectus, as
of a date not more than five days prior to the date of the bring-down letter),
the conclusions and findings of such firm with respect to the financial
information and other matters covered by the initial letters and (iii)
confirming in all material respects the conclusions and findings set forth in
the initial letter.

          (g) The Company shall have furnished to the Representatives a
certificate, dated such Delivery Date, of its Chairman of the Board, its
President, a Vice President or its chief financial officer or Treasurer stating
that:

                  (i) The representations, warranties and agreements of the
         Company in Section 1 are true and correct as of such Delivery Date; the
         Company has complied with all its agreements contained herein; and the
         conditions set forth in Sections 7(a), 7(h) and 7 (i) have been
         fulfilled; and

                 (ii) They have carefully examined the Registration Statement
         and the Prospectus and, in their opinion (A) as of the date of this
         Agreement, the Registration Statement and Prospectus did not include
         any untrue statement of a material fact and did not omit to state a
         material fact required to be stated therein or necessary to make the
         statements therein not misleading, and (B) since the date of this
         Agreement, no event has

                                       20
<PAGE>   21

         occurred which should have been set forth in a supplement or amendment
         to the Registration Statement or the Prospectus.

          (h) Since the date of the latest audited financial statements included
in the Prospectus (A) neither the Company nor any of the Significant
Subsidiaries shall have sustained any loss or interference with its business
from fire, explosion, flood or other calamity, whether or not covered by
insurance, or from any labor dispute or court or governmental action, order or
decree, otherwise than as set forth or contemplated in the Prospectus or (B)
there shall not have been any material change in the capital stock or long-term
debt of the Company or any of its subsidiaries or any change, or any development
involving a prospective change, in or affecting the consolidated financial
position, results of operations, business or prospects of the Company and its
subsidiaries, taken as a whole, otherwise than as set forth or contemplated in
the Prospectus, the effect of which, in any such case described in clause (A) or
(B), is, in the judgment of the Representatives, so material and adverse as to
make it impracticable or inadvisable to proceed with the public offering or the
delivery of the Stock being delivered on such Delivery Date on the terms and in
the manner contemplated in the Prospectus.

          (i) Subsequent to the execution and delivery of this Agreement there
shall not have occurred any of the following: (a) (i) trading in securities
generally on the New York Stock Exchange or the American Stock Exchange, or
trading in any securities of the Company on any exchange, shall have been
suspended or minimum prices shall have been established on any such exchange by
the Commission, by such exchange or by any other regulatory body or governmental
authority having jurisdiction, (ii) a general banking moratorium in New York
shall have been declared by Federal or New York state authorities, (iii) the
United States shall have become engaged in hostilities, there shall have been an
escalation in hostilities involving the United States or there shall have been a
declaration of a national emergency or war by the United States or (iv) there
shall have occurred a change in general economic, political or financial
conditions (or the effect of international conditions on the financial markets
in the United States shall be such) that in the judgment of the Representatives
is material and adverse and (b) in the case of any of the events specified in
clauses (a)(i) through (a)(iv) above, such event, singly or together with any
other such event, makes it, in the judgment of the Representatives,
impracticable or inadvisable to proceed with the public offering or delivery of
the Stock being delivered on such Delivery Date on the terms and in the manner
contemplated in the Prospectus.

         (j) The New York Stock Exchange, Inc. shall have approved the Stock for
listing, subject only to official notice of issuance.

                                       21
<PAGE>   22

         All opinions, letters, evidence and certificates mentioned above or
elsewhere in this Agreement shall be deemed to be in compliance with the
provisions hereof only if they are in form and substance reasonably satisfactory
to counsel for the Underwriters.

         SECTION 8. Indemnification and Contribution.

          (a) The Company shall indemnify and hold harmless each Underwriter,
its officers and employees and each person, if any, who controls any Underwriter
within the meaning of the Securities Act, from and against any loss, claim,
damage or liability, joint or several, or any action in respect thereof
(including, but not limited to, any loss, claim, damage, liability or action
relating to purchases and sales of Stock), to which that Underwriter, officer,
employee or controlling person may become subject, under the Securities Act or
otherwise, insofar as such loss, claim, damage, liability or action arises out
of, or is based upon, (i) any untrue statement or alleged untrue statement of a
material fact contained in (A) any Preliminary Prospectus, the Registration
Statement or the Prospectus or in any amendment or supplement thereto or (B) in
any materials or information provided to investors by, or with the approval of,
the Company in connection with the marketing of the offering of the Stock
("MARKETING MATERIALS"), including any roadshow or investor presentations made
to investors by the Company (whether in person or electronically) or (ii) the
omission or alleged omission to state in any Preliminary Prospectus, the
Registration Statement or the Prospectus, or in any amendment or supplement
thereto, or in any Marketing Materials, any material fact required to be stated
therein or necessary to make the statements therein not misleading, and shall
reimburse each Underwriter and each such officer, employee or controlling person
promptly upon demand for any legal or other expenses reasonably incurred by that
Underwriter, officer, employee or controlling person in connection with
investigating or defending or preparing to defend against any such loss, claim,
damage, liability or action as such expenses are incurred; provided, however,
that the Company shall not be liable in any such case to the extent that any
such loss, claim, damage, liability or action arises out of, or is based upon,
any untrue statement or alleged untrue statement or omission or alleged omission
made in any Preliminary Prospectus, the Registration Statement or the
Prospectus, or in any such amendment or supplement, in reliance upon and in
conformity with written information concerning such Underwriter furnished to the
Company through the Representatives by or on behalf of any Underwriter
specifically for inclusion therein, which information consists solely of the
information specified in Section 8(e); and, provided further, that the Company
will not be liable to any Underwriter with respect to any Preliminary Prospectus
to the extent the Company shall sustain the burden of proving that any such
loss, claim, damage or liability resulted from the fact that such Underwriter,
in contravention of a requirement of applicable law, sold Stock to a person to
whom such Underwriter failed to send or give, at or prior to the Closing Date, a
copy of

                                       22
<PAGE>   23

the Prospectus, as then amended or supplemented, if: (i) the Company has
previously furnished copies thereof (in sufficient quantity and sufficiently in
advance of the Closing Date to allow for distribution by the Closing Date) to
the Underwriter and the loss, claim, damage or liability of such Underwriter
resulted from an untrue statement or omission of a material fact contained in or
omitted from the Preliminary Prospectus which was corrected in the Prospectus
as, if applicable, amended or supplemented prior to the Closing Date and such
Prospectus was required by law to be delivered at or prior to the written
confirmation of sale to such person and (ii) such failure to give or send such
Prospectus by the Closing Date to the party or parties asserting such loss,
claim, damage or liability would have constituted the sole defense to the claim
asserted by such person. The foregoing indemnity agreement is in addition to any
liability which the Company may otherwise have to any Underwriter or to any
officer, employee or controlling person of that Underwriter.

          (b) Each Underwriter, severally and not jointly, shall indemnify and
hold harmless the Company, its officers and employees, each of its directors,
and each person, if any, who controls the Company within the meaning of the
Securities Act, from and against any loss, claim, damage or liability, joint or
several, or any action in respect thereof, to which the Company or any such
director, officer or controlling person may become subject, under the Securities
Act or otherwise, insofar as such loss, claim, damage, liability or action
arises out of, or is based upon, (i) any untrue statement or alleged untrue
statement of a material fact contained in any Preliminary Prospectus, the
Registration Statement or the Prospectus or in any amendment or supplement
thereto, or (ii) the omission or alleged omission to state in any Preliminary
Prospectus, the Registration Statement or the Prospectus, or in any amendment or
supplement thereto, any material fact required to be stated therein or necessary
to make the statements therein not misleading, but in each case only to the
extent that the untrue statement or alleged untrue statement or omission or
alleged omission was made in reliance upon and in conformity with written
information concerning such Underwriter furnished to the Company through the
Representatives by or on behalf of that Underwriter specifically for inclusion
therein, and shall reimburse the Company and any such director, officer or
controlling person for any legal or other expenses reasonably incurred by the
Company or any such director, officer or controlling person in connection with
investigating or defending or preparing to defend against any such loss, claim,
damage, liability or action as such expenses are incurred. The foregoing
indemnity agreement is in addition to any liability which any Underwriter may
otherwise have to the Company or any such director, officer, employee or
controlling person.

          (c) Promptly after receipt by an indemnified party under this Section
8 of notice of any claim or the commencement of any action, the indemnified
party shall, if a claim in respect thereof is to be made against the
indemnifying party

                                       23
<PAGE>   24

under this Section 8, notify the indemnifying party in writing of the claim or
the commencement of that action; provided, however, that the failure to notify
the indemnifying party shall not relieve it from any liability which it may have
under this Section 8 except to the extent it has been materially prejudiced by
such failure and, provided further, that the failure to notify the indemnifying
party shall not relieve it from any liability which it may have to an
indemnified party otherwise than under this Section 8. If any such claim or
action shall be brought against an indemnified party, and it shall notify the
indemnifying party thereof, the indemnifying party shall be entitled to
participate therein and, to the extent that it wishes, jointly with any other
similarly notified indemnifying party, to assume the defense thereof with
counsel reasonably satisfactory to the indemnified party. After notice from the
indemnifying party to the indemnified party of its election to assume the
defense of such claim or action, the indemnifying party shall not be liable to
the indemnified party under this Section 8 for any legal or other expenses
subsequently incurred by the indemnified party in connection with the defense
thereof other than reasonable costs of investigation; provided, however, that
the Representatives shall have the right to employ counsel to represent jointly
the Representatives and those other Underwriters and their respective officers,
employees and controlling persons who may be subject to liability arising out of
any claim in respect of which indemnity may be sought by the Underwriters
against the Company under this Section 8 if (i) the employment of such counsel
has been expressly authorized in writing by the Company; (ii) the Company has
not assumed the defense of and employed counsel reasonably satisfactory to the
Representatives within a reasonable time after notice of the commencement of
such action or (iii) the named parties to any such action or proceeding
(including impleaded parties) include both an indemnified party and the Company
and such indemnified party shall have been advised in writing by counsel that
there may be one or more legal defenses available to such indemnified party,
which are different from or additional to those available to the Company, and
such counsel's representation of such indemnified party and the Company in such
action or proceeding would give rise to a conflict of interest which would make
it improper for such counsel to represent both the indemnified party and the
Company (in which case the Company shall not have the right to assume the
defense of such action or proceeding on behalf of such indemnified party). The
Company shall not, in connection with any one such action or proceeding, or
separate but substantially similar or related actions or proceedings in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable for the reasonable fees and expenses of more than one separate firm for
the Underwriters and all such indemnified parties (in addition to any local
counsel), which firm will be designated by the Representatives, as
representative of the Underwriters, and the Company shall reimburse all such
reasonable fees and expenses as they are billed. No indemnifying party shall (i)
without the prior written consent of the indemnified parties (which consent
shall not be unreasonably withheld), settle or compromise or consent to the
entry of any judgment with respect to any pending

                                       24
<PAGE>   25

or threatened claim, action, suit or proceeding in respect of which
indemnification or contribution may be sought hereunder (whether or not the
indemnified parties are actual or potential parties to such claim or action)
unless such settlement, compromise or consent includes an unconditional release
of each indemnified party from all liability arising out of such claim, action,
suit or proceeding, or (ii) be liable for any settlement of any such action
effected without its written consent (which consent shall not be unreasonably
withheld), but if settled with the consent of the indemnifying party or if there
be a final judgment for the plaintiff in any such action, the indemnifying party
agrees to indemnify and hold harmless any indemnified party from and against any
loss or liability by reason of such settlement or judgment.

          (d If the indemnification provided for in this Section 8 shall for any
reason be unavailable to or insufficient to hold harmless an indemnified party
under Section 8(a) or 8(b) in respect of any loss, claim, damage or liability,
or any action in respect thereof, referred to therein, then each indemnifying
party shall, in lieu of indemnifying such indemnified party, contribute to the
amount paid or payable by such indemnified party as a result of such loss,
claim, damage or liability, or action in respect thereof, (i) in such proportion
as shall be appropriate to reflect the relative benefits received by the Company
on the one hand and the Underwriters on the other from the offering of the Stock
or (ii) if the allocation provided by clause (i) above is not permitted by
applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause (i) above but also the relative fault of
the Company on the one hand and the Underwriters on the other with respect to
the statements or omissions which resulted in such loss, claim, damage or
liability, or action in respect thereof, as well as any other relevant equitable
considerations. The relative benefits received by the Company on the one hand
and the Underwriters on the other with respect to such offering shall be deemed
to be in the same proportion as the total net proceeds from the offering of the
Stock purchased under this Agreement (before deducting expenses) received by the
Company, on the one hand, and the total underwriting discounts and commissions
received by the Underwriters with respect to the shares of the Stock purchased
under this Agreement, on the other hand, bear to the total gross proceeds from
the offering of the shares of the Stock under this Agreement, in each case as
set forth in the table on the cover page of the Prospectus. The relative fault
shall be determined by reference to whether the untrue or alleged untrue
statement of a material fact or omission or alleged omission to state a material
fact relates to information supplied by the Company or the Underwriters, the
intent of the parties and their relative knowledge, access to information and
opportunity to correct or prevent such statement or omission. The Company and
the Underwriters agree that it would not be just and equitable if contributions
pursuant to this Section were to be determined by pro rata allocation (even if
the Underwriters were treated as one entity for such purpose) or by any other
method of allocation which does not take into account the equitable

                                       25
<PAGE>   26

considerations referred to herein. The amount paid or payable by an indemnified
party as a result of the loss, claim, damage or liability, or action in respect
thereof, referred to above in this Section shall be deemed to include, for
purposes of this Section 8(d), any legal or other expenses reasonably incurred
by such indemnified party in connection with investigating or defending any such
action or claim. Notwithstanding the provisions of this Section 8(d), no
Underwriter shall be required to contribute any amount in excess of the amount
by which the total price at which the Stock underwritten by it and distributed
to the public was offered to the public exceeds the amount of any damages which
such Underwriter has otherwise paid or become liable to pay by reason of any
untrue or alleged untrue statement or omission or alleged omission. No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Securities Act) shall be entitled to contribution from any person who was
not guilty of such fraudulent misrepresentation. The Underwriters' obligations
to contribute as provided in this Section 8(d) are several in proportion to
their respective underwriting obligations and not joint.

          (e The Underwriters severally confirm and the Company acknowledges
that the statements with respect to the public offering of the Stock by the
Underwriters set forth on the cover page of, the statements concerning
over-allotments and the concession and reallowance figures appearing under the
caption "Underwriting" in, the Prospectus are correct and constitute the only
information concerning such Underwriters furnished in writing to the Company by
or on behalf of the Underwriters specifically for inclusion in the Registration
Statement and the Prospectus.

         SECTION 9. Defaulting Underwriters.

                                       26
<PAGE>   27

         If, on any Delivery Date, any Underwriter defaults in the performance
of its obligations under this Agreement, the remaining non-defaulting
Underwriters shall be obligated to purchase the Stock which the defaulting
Underwriter agreed but failed to purchase on such Delivery Date in the
respective proportions which the number of shares of the Firm Stock set opposite
the name of each remaining non-defaulting Underwriter in Schedule 1 hereto bears
to the total number of shares of the Firm Stock set opposite the names of all
the remaining non-defaulting Underwriters in Schedule 1 hereto; provided,
however, that the remaining non-defaulting Underwriters shall not be obligated
to purchase any of the Stock on such Delivery Date if the total number of shares
of the Stock which the defaulting Underwriter or Underwriters agreed but failed
to purchase on such date exceeds 9.09% of the total number of shares of the
Stock to be purchased on such Delivery Date, and any remaining non-defaulting
Underwriter shall not be obligated to purchase more than 110% of the number of
shares of the Stock which it agreed to purchase on such Delivery Date pursuant
to the terms of Section 3. If the foregoing maximums are exceeded, the remaining
non-defaulting Underwriters, or those other underwriters satisfactory to the
Representatives and the Company who so agree, shall have the right, but shall
not be obligated, to purchase, in such proportion as may be agreed upon among
them, all the Stock to be purchased on such Delivery Date. If the remaining
Underwriters or other underwriters satisfactory to the Representatives and the
Company do not elect to purchase the shares which the defaulting Underwriter or
Underwriters agreed but failed to purchase on such Delivery Date, this Agreement
(or, with respect to the Second Delivery Date, the obligation of the
Underwriters to purchase, and of the Company to sell, the Option Stock) shall
terminate without liability on the part of any non-defaulting Underwriter or the
Company, except that the Company will continue to be liable for the payment of
expenses to the extent set forth in Sections 6 and 11. As used in this
Agreement, the term "UNDERWRITER" includes, for all purposes of this Agreement
unless the context requires otherwise, any party not listed in Schedule 1 hereto
who, pursuant to this Section 9, purchases Stock which a defaulting Underwriter
agreed but failed to purchase.

         Nothing contained herein shall relieve a defaulting Underwriter of any
liability it may have to the Company for damages caused by its default. If other
underwriters are obligated or agree to purchase the Stock of a defaulting or
withdrawing Underwriter, either the Representatives or the Company may postpone
the Delivery Date for up to seven full business days in order to effect any
changes that in the opinion of counsel for the Company or counsel for the
Underwriters may be necessary in the Registration Statement, the Prospectus or
in any other document or arrangement.

         SECTION 10. Termination. The obligations of the Underwriters hereunder
may be terminated by the Representatives by notice given to and received by the
Company prior to delivery of and payment for the Firm Stock if, prior to that
time,

                                       27
<PAGE>   28

any of the events described in Sections 7(h) or 7(i), shall have occurred or if
the Underwriters shall decline to purchase the Stock for any reason permitted
under this Agreement.

         SECTION 11. Reimbursement of Underwriters' Expenses. If the Company
shall fail to tender the Stock for delivery to the Underwriters by reason of any
failure, refusal or inability on the part of the Company to perform any
agreement on its part to be performed, or because any other condition of the
Underwriters' obligations hereunder required to be fulfilled by the Company is
not fulfilled, the Company will reimburse the Underwriters for all reasonable
out-of-pocket expenses (including fees and disbursements of counsel) incurred by
the Underwriters in connection with this Agreement and the proposed purchase of
the Stock, and upon demand the Company shall pay the full amount thereof to the
Representatives. If this Agreement is terminated pursuant to Section 9 by reason
of the default of one or more Underwriters, the Company shall not be obligated
to reimburse any defaulting Underwriter on account of those expenses.

         SECTION 12. Notices, Etc. All statements, requests, notices and
agreements hereunder shall be in writing, and:

         (a) if to the Underwriters, shall be delivered or sent by mail, telex
or facsimile transmission to Lehman Brothers Inc., Three World Financial Center,
New York, New York 10285, Attention: Syndicate Department (Fax: 212-526-6588),
with a copy, in the case of any notice pursuant to Section 8(c), to the Director
of Litigation, Office of the General Counsel, Lehman Brothers Inc., 3 World
Financial Center, 10th Floor, New York, NY 10285;

         (b) if to the Company, shall be delivered or sent by mail, telex or
facsimile transmission to the address of the Company set forth in the
Registration Statement, Attention: General Counsel (Fax: (918) 573-5942);

provided, however, that any notice to an Underwriter pursuant to Section 8(c)
shall be delivered or sent by mail, telex or facsimile transmission to such
Underwriter at its address set forth in its acceptance telex to the
Representatives, which address will be supplied to any other party hereto by the
Representatives upon request. Any such statements, requests, notices or
agreements shall take effect at the time of receipt thereof. The Company shall
be entitled to act and rely upon any request, consent, notice or agreement given
or made on behalf of the Underwriters by Lehman Brothers Inc. on behalf of the
Representatives.

         SECTION 13. Persons Entitled to Benefit of Agreement. This Agreement
shall inure to the benefit of and be binding upon the Underwriters, the Company,
and their respective successors. This Agreement and the terms and provisions
hereof are for the sole benefit of only those persons, except that (A) the

                                       28
<PAGE>   29

representations, warranties, indemnities and agreements of the Company contained
in this Agreement shall also be deemed to be for the benefit of the person or
persons, if any, who control any Underwriter within the meaning of Section 15 of
the Securities Act and (B) the indemnity agreement of the Underwriters contained
in Section 8(b) of this Agreement shall be deemed to be for the benefit of
directors of the Company, officers of the Company who have signed the
Registration Statement and any person controlling the Company within the meaning
of Section 15 of the Securities Act. Nothing in this Agreement is intended or
shall be construed to give any person, other than the persons referred to in
this Section 13, any legal or equitable right, remedy or claim under or in
respect of this Agreement or any provision contained herein.

         SECTION 14. Survival. The respective indemnities, representations,
warranties and agreements of the Company and the Underwriters contained in this
Agreement or made by or on behalf on them, respectively, pursuant to this
Agreement, shall survive the delivery of and payment for the Stock and shall
remain in full force and effect, regardless of any investigation made by or on
behalf of any of them or any person controlling any of them.

         SECTION 15. Definition of the Terms "BUSINESS DAY" and "SUBSIDIARY" .
For purposes of this Agreement, (a) "BUSINESS DAY" means each Monday, Tuesday,
Wednesday, Thursday or Friday which is not a day on which banking institutions
in New York are generally authorized or obligated by law or executive order to
close and (b) "SUBSIDIARY" has the meaning set forth in Rule 405 of the Rules
and Regulations.

         SECTION 16. Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of New York.

         SECTION 17. Counterparts. This Agreement may be executed in one or more
counterparts and, if executed in more than one counterpart, the executed
counterparts shall each be deemed to be an original but all such counterparts
shall together constitute one and the same instrument.

         SECTION 18. Headings. The headings herein are inserted for convenience
of reference only and are not intended to be part of, or to affect the meaning
or interpretation of, this Agreement.

                                       29
<PAGE>   30

         If the foregoing correctly sets forth the agreement between the Company
and the Underwriters, please indicate your acceptance in the space provided for
that purpose below.

Very truly yours,

THE WILLIAMS COMPANIES, INC.

By /s James G. Ivey
   ----------------

Name: James G. Ivey

Title: Treasurer

Accepted:

LEHMAN BROTHERS INC.
MERRILL LYNCH, PIERCE,
   FENNER & SMITH INCORPORATED
CREDIT SUISSE FIRST BOSTON CORPORATION

For themselves and as Representatives
of the several Underwriters named
in Schedule 1 hereto

By   LEHMAN BROTHERS INC.

By       /s   (illegible)
   ------------------------------
    Authorized Representative

By   MERRILL LYNCH, PIERCE, FENNER
         & SMITH INCORPORATED

By       /s  (illegible)
   --------------------------------
     Authorized Representative

                                       30
<PAGE>   31

                                            SCHEDULE 1

<TABLE>
<CAPTION>
                                                                Number of Shares of Firm
                         Underwriters                           Stock to be Purchased
<S>                                                             <C>
Lehman Brothers Inc..........................................                  8,800,000
Merrill Lynch, Pierce, Fenner &
   Smith Incorporated........................................                  8,800,000
Credit Suisse First Boston Corporation.......................                  8,800,000
Banc of America Securities LLC. .............................                  1,650,000
CIBC World Markets Corp. ....................................                  1,650,000
Goldman, Sachs & Co. ........................................                  1,650,000
UBS Warburg LLC..............................................                  1,650,000
Total........................................................                 33,000,000
</TABLE>

<PAGE>   32

                                   SCHEDULE 2

                            Significant Subsidiaries

Williams Gas Pipeline Company, LLC
Transcontinental Gas Pipe Line Corporation
Williams Gas Pipelines Central, Inc.
Northwest Pipeline Corporation
Texas Gas Transmission Corporation
Kern River Gas Transmission Company
Williams Energy Services, LLC
Williams Communications Group, Inc.

<PAGE>   33

                                                                       EXHIBIT A

                            LOCK-UP LETTER AGREEMENT

LEHMAN BROTHERS INC.
MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED
CREDIT SUISSE FIRST BOSTON CORPORATION

As Representatives of the several
  Underwriters named in Schedule 1
c/o Lehman Brothers Inc.
Three World Financial Center
New York, New York 10285

Dear Sirs:

         The undersigned understands that you and certain other firms propose to
enter into an Underwriting Agreement (the "UNDERWRITING AGREEMENT") providing
for the purchase by you and such other firms (the "UNDERWRITERS") of shares (the
"SHARES") of Common Stock, par value $1.00 per share (the "COMMON STOCK"), of
The Williams Companies, Inc., a Delaware corporation (the "COMPANY"), and that
the Underwriters propose to reoffer the Shares to the public (the "OFFERING").

         In consideration of the execution of the Underwriting Agreement by the
Underwriters, and for other good and valuable consideration, the undersigned
hereby irrevocably agrees that, without the prior written consent of Lehman
Brothers Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated, on behalf
of the Underwriters, the undersigned will not, directly or indirectly, (1) offer
for sale, sell, pledge, or otherwise dispose of (or enter into any transaction
or device that is designed to, or could be expected to, result in the
disposition by any person at any time in the future of) any shares of Common
Stock (including, without limitation, shares of Common Stock that may be deemed
to be beneficially owned by the undersigned in accordance with the rules and
regulations of the Securities and Exchange Commission and shares of Common Stock
that may be issued upon exercise of any option or warrant) or securities
convertible into or exchangeable for Common Stock (other than the Shares) owned
by the undersigned on the date of execution of this Lock-Up Letter Agreement or
on the date of the completion of the Offering, or (2) enter into any swap or
other derivatives transaction that transfers to another, in whole or in part,
any of the economic benefits or risks of ownership of such shares of Common
Stock, whether any such transaction described in clause (1) or (2) above is to
be settled by delivery of Common Stock

<PAGE>   34

or other securities, in cash or otherwise, for a period of 90 days after the
date of the final Prospectus relating to the Offering.

         In furtherance of the foregoing, the Company and its Transfer Agent are
hereby authorized to decline to make any transfer of securities if such transfer
would constitute a violation or breach of this Lock-Up Letter Agreement.

         It is understood that, if the Company notifies you that it does not
intend to proceed with the Offering, if the Underwriting Agreement does not
become effective, or if the Underwriting Agreement (other than the provisions
thereof which survive termination) shall terminate or be terminated prior to
payment for and delivery of the Shares, we will be released from our obligations
under this Lock-Up Letter Agreement.

         The undersigned understands that the Company and the Underwriters will
proceed with the Offering in reliance on this Lock-Up Letter Agreement.

         Whether or not the Offering actually occurs depends on a number of
factors, including market conditions. Any Offering will only be made pursuant to
an Underwriting Agreement, the terms of which are subject to negotiation between
the Company and the Underwriters.

                                       2
<PAGE>   35

         The undersigned hereby represents and warrants that the undersigned has
full power and authority to enter into this Lock-Up Letter Agreement and that,
upon request, the undersigned will execute any additional documents necessary in
connection with the enforcement hereof. Any obligations of the undersigned shall
be binding upon the heirs, personal representatives, successors and assigns of
the undersigned.

                                            Very truly yours,

                                            By:
                                               ---------------------------------
                                               Name:
                                               Title:

Dated:
       ----------------------

                                       3<PAGE>   1
                                                                   EXHIBIT 10.10

                                 AMENDMENT NO. 3
                   TO AMTC CORPORATION STOCK OPTION AGREEMENT

         This Amendment No. 3 is entered into as of November 2, 2000, between
David P. Cook ("Cook") and ZixIt Corporation, a Texas corporation ("ZixIt").
Reference is made to that certain AMTC Corporation Stock Option Agreement,
effective as of April 29, 1998, as amended, between Cook and ZixIt (the "Cook
Option").

1. Amendments. The Cook Option is amended to delete "2,627,777" from Section 1
and substitute in its place "2,375,277." (Note: 2,375,277 shares is the number
of shares covered by the Cook Option after giving effect to all previous
re-allocations of option shares by Mr. Cook. Furthermore, giving effect to the
March 2000 option exercise and all previous re-allocations by Mr. Cook, the
number of option shares remaining under the Cook Option is 2,123,577.)

2. No Other Changes. Other than as provided herein, the Cook Option shall remain
in full force and effect.

         Executed on the dates set forth below, to be effective as of the date
first set forth above.

                                       ZIXIT CORPORATION

                                       By:       /s/ Steve York
                                                -------------------------------
                                                Steve M. York,
                                                Senior Vice President

                                       Date:    3/9/01
                                                -------------------------------

                                       /s/ David P. Cook
                                       ----------------------------------------
                                       David P. Cook

                                       Date:    3/9/01
                                                -------------------------------

                                       /s/ Cheryl G. Cook
                                       ----------------------------------------
                                       Cheryl G. Cook

                                       Date:    3/9/01
                                                -------------------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}]]