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                                                                    EXHIBIT 3(b)

                              BY-LAWS - AT&T CORP.
                      AS AMENDED BY THE BOARD OF DIRECTORS

     ON DECEMBER 6, 2000, JANUARY 25, 2001, NOVEMBER 14, 2002 AND MARCH 20,
                                      2003

                                   ARTICLE I.

                             MEETING OF SHAREHOLDERS

         Section 1. The annual meeting of the shareholders of the company shall
be held on such date, at such time and at such place as may be fixed by
resolution of the Board of Directors.

         A notice of the annual meeting as approved by the Board of Directors
shall be mailed not less than ten nor more than sixty days before the meeting,
directed to each shareholder entitled to vote at said meeting at his address as
it appears on the record of shareholders unless he shall have filed with the
Secretary a written request that notices intended for him be mailed to some
other address, in which case it shall be directed to him at such other address.

         Section 2. The Board of Directors may fix, in advance, a date not more
than sixty nor less than ten days before the date of any meeting of the
shareholders as the record date for determination of shareholders entitled to
notice of or to vote at such meeting, and only shareholders of record on such
date shall be entitled to notice of or to vote at such meeting.

         Section 3. Subject to the rights of the holders of any series of stock
having a preference over the common stock and except as may otherwise be
required by law, special meetings of the shareholders may be called at any time
only by the Chairman of the Board or the Board of Directors. The meeting shall
be held at such place within or without the State of New York as may be
designated in the notice of the meeting.

         A notice of not less than ten nor more than sixty days shall be given
by mail for each special meeting, in the manner provided for notice of the
annual meeting. Such notice shall state the purpose or purposes for which the
meeting is called and the time when and the place where it is to be held and
shall indicate that the notice is being issued by or at the direction of the
person or persons calling the meeting.

         Section 4. Failure to receive notice of any meeting shall not
invalidate the meeting.

         Section 5. (A) Nominations of persons for election to the Board of
Directors of the company and notice of shareholders business at meetings of
shareholders shall be governed by the provisions of this By-Law.

                           (1) Nominations of persons for election to the Board
                  of Directors of the company, and the proposal of business to
                  be considered by the shareholders, may be made at an annual
                  meeting of shareholders only (a) pursuant to the company's
                  notice of meeting pursuant to Article I of these By-Laws, (b)
                  by or at the direction of the Board of Directors or (c) by any
                  shareholder of the company who was a shareholder of record at
                  the time of giving notice provided for in this By-Law,

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                  who is entitled to vote at the meeting and who complies with
                  the notice procedures set forth in this By-Law.

                           (2) For nominations or other business to be properly
                  brought before an annual meeting by a shareholder pursuant to
                  clause (c) of paragraph (A)(1) of this By-Law, the shareholder
                  must have given timely notice thereof in writing to the
                  Secretary of the company and such other business must
                  otherwise be a proper matter for shareholder action. To be
                  timely, a shareholder's notice shall be delivered to the
                  Secretary at the principal executive offices of the company
                  not later than the close of business on the 90th calendar day
                  nor earlier than the close of business on the 120th calendar
                  day prior to the first anniversary of the preceding year's
                  annual meeting; provided, however, that in the event that the
                  date of the annual meeting is more than 30 calendar days
                  before or more than 60 calendar days after such anniversary
                  date, notice by the shareholder to be timely must be so
                  delivered not earlier than the close of business on the 120th
                  calendar day prior to such annual meeting but not later than
                  the close of business on the later of the 90th calendar day
                  prior to such annual meeting or the 10th calendar day
                  following the calendar day on which public announcement of the
                  date of such meeting is first made by the company. In no event
                  shall the public announcement of an adjournment of an annual
                  meeting commence a new time period for the giving of a
                  shareholder's notice as described above. Such shareholder's
                  notice shall set forth (a) as to each person whom the
                  shareholder proposes to nominate for election or reelection as
                  a director all information relating to such person that is
                  required to be disclosed in solicitations of proxies for
                  election of directors in an election contest, or is otherwise
                  required, in each case pursuant to Regulation 14A under the
                  Securities Exchange Act of 1934, as amended (the "Exchange
                  Act") and Rule 14a-11 thereunder (including such person's
                  written consent to being named in the proxy statement as a
                  nominee and to serving as a director if elected); (b) as to
                  any description of any other business desired to be brought
                  before the meeting, the reasons for conducting such other
                  business at the meeting and any material interest in such
                  other business of such shareholder and beneficial owner, if
                  any, on whose behalf the proposal is made; and (c) as to the
                  shareholder giving the notice and the beneficial owner, if
                  any, on whose behalf the nomination or proposal is made (i)
                  the name and address of such shareholder, as they appear on
                  the company's books, and of such beneficial owner and (ii) the
                  class and number of shares of the company which are owned
                  beneficially and of record by such shareholder and such
                  beneficial owner.

                           (3) Notwithstanding anything in the second sentence
                  of paragraph (A)(2) of this By-Law to the contrary, in the
                  event that the number of directors to be elected to the Board
                  of Directors of the company is increased and there is no
                  public announcement by the company naming all of the nominees
                  for director or specifying the size of the increased Board of
                  Directors at least 100 days prior to the first anniversary of
                  the preceding year's annual meeting, a shareholder's notice
                  required by this By-Law shall also be considered timely, but
                  only with respect to nominees for any new positions created by
                  such increase, if it shall be delivered to the Secretary at
                  the principal executive offices of the company not later than

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                  the close of business on the 10th day following the day on
                  which such public announcement is first made by the company.

                  (B) Special Meetings of Stockholders. Nominations of persons
for election to the Board of Directors may be made at a special meeting of
shareholders at which directors are to be elected pursuant to the company's
notice of meeting (a) by or at the direction of the Board of Directors or (b)
provided that the Board of Directors has determined that directors shall be
elected at such meeting, by any shareholder of the company who is a shareholder
of record at the time of giving of notice provided for in this By-Law, who shall
be entitled to vote at the meeting and who complies with the notice procedures
set forth in this By-Law. In the event the company calls a special meeting of
shareholders for the purpose of electing one or more directors to the Board of
Directors, any such shareholder may nominate a person or persons (as the case
may be), for election to such position(s) as specified in the company's notice
of meeting, if the shareholder's notice required by paragraph (A)(2) of this
By-Law shall be delivered to the Secretary at the principal executive offices of
the company not earlier than the close of business on the 120th day prior to
such special meeting and not later than the close of business on the later of
the 90th day prior to such special meeting or the 10th day following the day on
which public announcement is first made of the date of the special meeting and
of the nominees proposed by the Board of Directors to be elected at such
meeting. In no event shall the public announcement of an adjournment of a
special meeting commence a new time period for the giving of a shareholder's
notice as described above.

                  (C) General. (1) Only such persons who are nominated in
accordance with the procedures set forth in this By-Law shall be eligible to
serve as directors and only such business shall be conducted at a meeting of
shareholders as shall have been brought before the meeting in accordance with
the procedures set forth in this By-Law. Except as otherwise provided by law,
the Chairman of the meeting shall have the power and duty to determine whether a
nomination or any business proposed to be brought before the meeting was made or
proposed, as the case may be, in accordance with the procedures set forth in
this By-Law and, if any proposed nomination or business is not in compliance
with this By-Law, to declare that such defective proposal or nomination shall be
disregarded.

         (2) For purposes of this By-Law, "public announcement" shall mean
disclosure in a press release reported by the Dow Jones News Service, Associated
Press or comparable national news service or in a document publicly filed by the
company with the Securities and Exchange Commission pursuant to Section 13, 14
or 15(d) of the Exchange Act.

         (3) Notwithstanding the foregoing provisions of this By-Law, a
shareholder shall also comply with all applicable requirements of the Exchange
Act and the rules and regulations thereunder with respect to the matters set
forth in this By-Law. Nothing in this By-Law shall be deemed to affect any
rights (i) of shareholders to request inclusion of proposals in the company's
proxy statement pursuant to Rule 14a-8 under the Exchange Act or (ii) of the
holders of any series of Preferred Stock to elect directors under specified
circumstances.

         Section 6. The Chairman of the Board of Directors may postpone or
adjourn any meeting of the shareholders from time to time, whether or not a
quorum is present. The chair of the meet-

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ing shall determine all matters relating to the efficient conduct of the
meeting, including but not limited to the maintenance of order and decorum.

                                  ARTICLE II.

                      THE CONDUCT OF SHAREHOLDERS' MEETINGS

         At all meetings of the shareholders, the holders of forty per centum of
the shares entitled to vote thereat shall constitute a quorum, except as
otherwise required by law; but the shareholders present may adjourn the meeting
to another time or place despite the absence of a quorum. Every shareholder
entitled to vote shall be entitled to one vote for each share standing in his
name on the record of shareholders; and every shareholder entitled to vote may
vote in person or by proxy.

         At all meetings of shareholders, a shareholder, or such person's duly
authorized attorney in fact, may vote by proxy, executed in writing or granted
or authorized in such other manner as is prescribed by the Business Corporation
Law of the State of New York.

         Except as otherwise required by law or as specified in the company's
certificate of incorporation, every shareholder entitled to vote shall be
entitled to one vote for each share standing in his name on the record of
shareholders; and every shareholder entitled to vote may vote in person or by
proxy.

                                  ARTICLE III.

                                   INSPECTORS

         The Board of Directors, in advance of any shareholders' meeting, shall
appoint one inspector to act at the meeting or any adjournment thereof. In case
any person appointed fails to appear or act, the vacancy may be filled by
appointment made by the Board in advance of the meeting or at the meeting by the
person presiding thereat.

                                  ARTICLE IV.

                             THE BOARD OF DIRECTORS

         Section 1. The business of the company shall be managed under the
direction of its Board of Directors, who shall be elected by the shareholders at
the annual meeting.

         Section 2. The number of Directors shall be not less than nine nor more
than twenty-five, the exact number of Directors within such minimum and maximum
limits to be fixed and determined by the vote of a majority of the entire Board.

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                                   ARTICLE V.

                              MEETINGS OF DIRECTORS

         Section 1. Regular meetings shall be held at such times and places as
the Board may determine.

         Section 2. Special meetings of the Directors may be called at any time
by the Chairman of the Board, or by two members of the Executive Committee, and
shall be called by the Chairman of the Board, or by the Secretary, forthwith
upon request in writing signed by two Directors and specifying the object of the
meeting. At least three days' notice of a special meeting shall be given in the
manner provided for herein.

         Section 3. Any notice of a meeting of Directors required to be given
may be given to each Director by mail or telegraph, addressed to him at his
residence or usual place of business, or in person or by telephone, stating the
time and place of the proposed meeting.

         Section 4. One-third of the entire Board shall constitute a quorum.

         Section 5. Meetings of the Directors may be held within or without the
State of New York.

         Section 6. Any one or more members of the Board may participate in a
meeting of the Board by means of a conference telephone or similar
communications equipment allowing all persons participating in the meeting to
hear each other at the same time. Participation by such means shall constitute
presence in person at a meeting.

         Any action required or permitted to be taken by the Board may be taken
without a meeting if all members of the Board consent in writing to the adoption
of a resolution authorizing the action. The resolution and the written consents
thereto by the members of the Board shall be filed with the minutes of the
proceedings of the Board.

                                   ARTICLE VI.

                    EXECUTIVE COMMITTEE AND OTHER COMMITTEES

         The Board of Directors, by resolution adopted by a majority of the
entire Board, may designate from their number an Executive Committee and other
committees, and may determine the quorum thereof. Any such committee shall
consist of three or more members and shall serve at the pleasure of the Board.

         The Chairman of the Board, one or more Vice Chairmen of the Board and
the President, if any, shall be members of the Executive Committee. The
Executive Committee shall, except as otherwise provided by law or by resolution
of the Board, have all the authority of the Board of Directors during the
intervals between the meetings of the Board. The Executive Committee shall keep
a record of its proceedings, which shall from time to time be reported to the
Board of Directors. The Chairman of the Board shall preside at the meetings of
the Executive Committee.

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         Committees other than the Executive Committee shall, except as
otherwise provided by law, have such authority as shall be provided by
resolution of the Board.

         The Board may designate from time to time one or more Directors as
alternate members of the Executive Committee or of any other committee, who may
replace any absent member or members at any meeting of the committee.

         Any one or more members of the Executive Committee or any other
committee established by the Board pursuant to this Article VI may participate
in a meeting of such committee by means of a conference telephone or similar
communications equipment allowing all persons participating in the meeting to
hear each other at the same time. Participation by such means shall constitute
presence in person at the meeting.

         Any action required or permitted to be taken by the Executive Committee
or any other committee established by the Board pursuant to this Article VI may
be taken without a meeting if all members of the committee consent in writing to
the adoption of a resolution authorizing the action. The resolution and written
consents thereto shall be filed with the minutes of the proceedings of the
committee.

         The Board of Directors shall form a Capital Stock Committee, which
committee shall consist of one director elected pursuant to Section 7.15 of the
Agreement and Plan of Restructuring and Merger, dated June 23, 1998, among the
Corporation, Italy Merger Corp. and Tele-Communications, Inc. and three
directors who are not current or former officers, directors or employees of the
Corporation or any of its affiliates, or otherwise affiliated with the
Corporation (other than as members of the Board of Directors or any committee
thereof). The Liberty Media Group Capital Stock Committee shall have the
authority of the Board of Directors to (i) interpret, make determinations under,
and oversee the implementation of the policies set forth in the policy statement
regarding Liberty Media Group tracking stock matters adopted by resolution of a
majority of the entire Board, and (ii) to the extent permitted by law, to take
all actions required to be taken by the Board of Directors of the company in
connection with authorization of the issuance of shares of Liberty Media Group
tracking stock.

         The Board of Directors may form an AT&T Wireless Group Capital Stock
Committee, the members of which shall be selected by the board of directors. The
Board may delegate to the AT&T Wireless Group Capital Stock Committee the
authority to, and the AT&T Wireless Group Capital Stock Committee will thereby
have the authority to, (i) interpret, make determinations under, and oversee the
implementation of the policies set forth in the Policy Statement Regarding AT&T
Wireless Group Tracking Stock Matters; (ii) review the policies, programs and
practices of the company relating to (a) the business and financial
relationships between the company or any of its units (other than the Liberty
Media Group) and the AT&T Wireless Group, (b) dividends in respect of,
disclosures to shareholders and the public concerning, and transactions by the
company or any of its subsidiaries (other than subsidiaries included in the
Liberty Media Group) in, shares of AT&T Wireless Group Tracking Stock, and (c)
any matters arising in connection therewith, all to the extent the AT&T Wireless
Group Capital Stock Committee may deem appropriate; and (iii) recommend such
changes in such policies, programs and practices as the AT&T Wireless Group
Capital Stock Committee may deem appropriate. In performing this function, the
AT&T Wireless Group Capital Stock Committee's role shall not be to make
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sions concerning matters referred to its attention, but, rather, to oversee
the process by which decisions concerning such matters are made. The AT&T
Wireless Group Capital Stock Committee shall have and may exercise such other
powers, authority and responsibilities as may be determined from time to time by
the Board of Directors.

                                  ARTICLE VII.

                             OFFICERS OF THE COMPANY

         Section 1. The officers of the company shall be elected by the Board of
Directors, and may consist of a Chairman of the Board, one or more Vice Chairmen
of the Board, a President, such number of Executive Vice Presidents and Senior
Vice Presidents as the Board of Directors shall from time to time determine, a
Secretary, a Treasurer and a Controller. The officers shall hold office until
their successors have been elected.

         Section 2. The Board of Directors may appoint one or more Assistant
Secretaries, one or more Assistant Treasurers, one or more Assistant
Controllers, and such other officers and agents as the Board may consider
necessary.

                                 ARTICLE VIII.

                      DUTIES OF THE CHAIRMAN OF THE BOARD,
                     PRESIDENT, VICE CHAIRMEN OF THE BOARD,
              EXECUTIVE VICE PRESIDENTS AND SENIOR VICE PRESIDENTS

         Section 1. The Chairman of the Board shall be the chief executive
officer of the company and shall have such authority and perform such duties as
usually appertain to the chief executive office in business corporations. He
shall preside at the meetings of the Board of Directors and he, or such officer
as he may designate from time to time, shall preside at meetings of the
shareholders.

         Section 2. The President, Vice Chairmen of the Board, Executive Vice
Presidents and Senior Vice Presidents shall perform such duties as the Board of
Directors or Chairman of the Board may from time to time determine.

         Section 3. In case of absence or inability of the Chairman of the
Board, the President shall possess all the authority of the Chairman of the
Board.

                                  ARTICLE IX.

                DUTIES OF THE TREASURER AND ASSISTANT TREASURERS

         Section 1. The Treasurer shall receive all the funds of the company,
and shall disburse them under the direction of the Board of Directors. All
disbursement instruments shall be signed by such person or persons and in such
manner as the Board may from time to time provide.

         Section 2. The Treasurer shall keep full and regular books, showing all
his receipts and disbursements, which books shall be open at all times to the
inspection of the Chairman of the

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Board or of any member of the Board of Directors; and he shall make such reports
and perform such other duties as the Chairman of the Board or Board of Directors
may require.

         Section 3. The Treasurer shall deposit all moneys received by him, in
the corporate name of the company, with such depositories as shall be approved
from time to time by the Board of Directors or by the Chairman of the Board, the
President, a Vice Chairman of the Board or the Treasurer.

         Section 4. Assistant Treasurers shall have such of the authority and
perform such of the duties of the Treasurer as may be provided in these By-Laws
or assigned to them by the Board of Directors or the Chairman of the Board or by
the Treasurer upon the approval of the Chairman of the Board, the President or a
Vice Chairman of the Board. During the Treasurer's absence or inability, his
authority and duties shall be possessed by such Assistant Treasurer or Assistant
Treasurers as the Board of Directors, the Chairman of the Board, the President
or a Vice Chairman of the Board may designate.

         Section 5. The Board of Directors may require the Treasurer and
Assistant Treasurers to give such security for the faithful performance of their
duties as the Board shall from time to time determine.

                                   ARTICLE X.

                DUTIES OF THE SECRETARY AND ASSISTANT SECRETARIES

         Section 1. The Secretary shall send notice to the shareholders of all
annual and special meetings, and to the Directors of meetings of the Board where
notice is required to be given; and he shall perform such other duties as may be
required of him by the Chairman of the Board or Board of Directors, and such as
usually appertain to the office of Secretary.

         Section 2. The Secretary or in his absence an Assistant Secretary shall
keep an accurate record of the proceedings of the Board of Directors and of the
Executive Committee, and of all meetings of shareholders, and shall have the
custody of the seal of the company and affix it to all instruments requiring the
seal.

         Section 3. Assistant Secretaries shall have such of the authority and
perform such of the duties of the Secretary as may be provided in these By-Laws
or assigned to them by the Board of Directors or the Chairman of the Board or by
the Secretary upon the approval of the Chairman of the Board, the President or a
Vice Chairman of the Board. During the Secretary's absence or inability, his
authority and duties shall be possessed by such Assistant Secretary or Assistant
Secretaries as the Board of Directors, the Chairman of the Board, the President
or a Vice Chairman of the Board may designate.

                                  ARTICLE XI.

                            DUTIES OF THE CONTROLLER

         The Controller shall be the principal accounting officer of the company
and shall perform such duties as may be required of him by the Chairman of the
Board or Board of Directors.

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                                  ARTICLE XII.

                               TRANSFER OF SHARES

         Section 1. Shares shall be issued by the Treasurer in uncertificated
form pursuant to the customary arrangements for issuing shares in such form.
Shares shall be transferable only on the record of shareholders of the company
by the holder thereof in person or by attorney, upon compliance with the
customary procedures for transferring shares in uncertificated form or upon
surrender of the outstanding certificate therefore.

         Section 2. In case of the loss of a certificate, a new certificate may
be issued upon such terms as the Board of Directors may prescribe.

                                  ARTICLE XIII.

                    INDEMNIFICATION OF DIRECTORS AND OFFICERS

         The company is authorized, by (i) a resolution of shareholders, (ii) a
resolution of Directors, or (iii) an agreement providing for such
indemnification, to the fullest extent permitted by applicable law, to provide
indemnification and to advance expenses to its Directors and officers in respect
of claims, actions, suits or proceedings based upon, arising from, relating to
or by reason of the fact that any such Director or officer serves or served in
such capacity with the company or at the request of the company in any capacity
with any other enterprise.

                                  ARTICLE XIV.

                                      SEAL

         The common seal of the company shall be in the following form.

                                  ARTICLE XV.

                                   AMENDMENTS

         These By-Laws may be amended by the shareholders at any meeting; or by
the Board of Directors at any meeting by a majority vote of the full Board, or
at two successive meetings of the Board by a majority vote of a quorum present,
provided that the third paragraph of Article II shall not be rescinded, amended
or waived except at a shareholders meeting in accordance with applicable state
law. The notice of a special meeting of the Board at which such action is to be
taken shall set forth the substance of the proposed amendment.