COMCAST CORPORATION

                             1987 STOCK OPTION PLAN

             (As Amended and Restated, Effective December 10, 1996)


          1. Purpose. COMCAST CORPORATION, a Pennsylvania corporation (the
"Company"), adopts the Comcast Corporation 1987 Stock Option Plan effective
January 5, 1987 (the "Plan"). The Plan is intended as an additional incentive to
employees and non-employee members of the Board of Directors (together the
"Optionees") to enter into or remain in the employ of the Company or any
Affiliate (as defined below) or to serve on the Board of Directors of the
Company or any Affiliate and to devote themselves to the Company's success by
providing them with an opportunity to acquire or increase their proprietary
interest in the Company through receipt of rights (the "Options") to acquire the
Company's Class A Special Common Stock, par value, $1.00 per share (except as
otherwise provided in Section 12, the "Common Stock"). Each Option granted under
the Plan to an employee of the Company or an Affiliate is intended to be an
incentive stock option ("ISO") within the meaning of Section 422(b) of the
Internal Revenue Code of 1986, as amended (the "Code") for federal income tax
purposes, except to the extent any such ISO grant would exceed the limitation of
subsection 6(a) and except for any Option specifically designated at the time of
grant as not being an ISO. No Option granted to a person who is not an employee
of the Company or any Affiliate on the date of grant shall be an ISO. For
purposes of the Plan, except as otherwise provided in Section 14, the term
"Affiliate" shall mean a corporation which is a parent corporation or a
subsidiary corporation with respect to the Company within the meaning of Section
424(e) or (f) of the Code.

          2. Administration. The Plan shall be administered by the Subcommittee
on Performance Based Compensation of the Compensation Committee or any other
committee or subcommittee designated by the Board of Directors of the Company,
provided it is composed of two or more non-employee members of the Board of
Directors each of whom is an "outside director" within the meaning of Section
162(m)(4)(C) of the Code and applicable Treasury Regulations thereunder (the
"Committee"). Notwithstanding the foregoing, in the case non-employee directors
who are granted Options in accordance with the provisions of Section 8, the
directors to whom such Options will be granted, the timing of grants of such
Options, the Option Price (as such term is defined in subsection 6(b)) of such
Options and the number of Option Shares (as such term is defined in Section 4)
included in such Options shall be as specifically set forth in Section 8.

               (a) Meetings. The Committee shall hold meetings at such times and
places as it may determine. Acts approved at a meeting by a majority of the
members of the Committee or acts approved in writing by the unanimous consent of
the members of the Committee shall be the valid acts of the Committee.

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               (b) Grants. Except with respect to options granted to
non-employee directors pursuant to Section 8, the Committee shall from time to
time at its discretion direct the Company to grant Options pursuant to the terms
of the Plan. The Committee shall have plenary authority to determine the
Optionees to whom and the times at which Options shall be granted, the number of
Option Shares (as defined in Section 4) to be granted and the price and other
terms and conditions thereof, including a specification with respect to whether
an Option is intended to be an ISO, subject, however, to the express provisions
of the Plan. In making such determinations the Committee may take into account
the nature of the Optionee's services and responsibilities, the Optionee's
present and potential contribution to the Company's success and such other
factors as it may deem relevant. Notwithstanding the foregoing, grants of
Options to non-employee directors shall be made in accordance with Section 8.
The interpretation and construction by the Committee of any provision of the
Plan or of any Option granted under it shall be final, binding and conclusive.

               (c) Exculpation. No member of the Board of Directors or of the
Committee shall be personally liable for monetary damages as such for any action
taken or any failure to take any action in connection with the administration of
the Plan or the granting of Options under it unless (i) the director or member
of the Committee has breached or failed to perform the duties of his office and
(ii) the breach or failure to perform constitutes self-dealing, willful
misconduct or recklessness; provided, however, that the provisions of this
subsection 2(c) shall not apply to the responsibility or liability of a director
or a member of the Committee pursuant to any criminal statute.

               (d) Indemnification. Each member of the Board of Directors or of
the Committee shall be entitled without further act on his part to indemnity
from the Company to the fullest extent provided by applicable law and the
Company's by-laws in connection with or arising out of any action, suit or
proceeding with respect to the administration of the Plan or the granting of
Options under it in which he may be involved by reason of his being or having
been a member of the Board of Directors or the Committee, whether or not he
continues to be such member of the Board or the Committee at the time of the
action, suit or proceeding.

          3. Eligibility. All employees of the Company or its Affiliates (who
may also be directors of the Company or its Affiliates) shall be eligible to
receive ISOs hereunder. All Optionees shall be eligible to receive Options
hereunder. The Committee, in its sole discretion, shall determine whether an
individual qualifies as an employee or as an Optionee. An Optionee may receive
more than one Option, but only on the terms and subject to the restrictions of
the Plan, provided, however, that non-employee directors may receive Options
only pursuant to Section 8.

          4. Option Shares. The aggregate maximum number of shares of the Common
Stock for which Options may be issued under the Plan is 19,500,000 shares,
adjusted as provided in Section 9 (the "Option Shares"). Option Shares shall be
issued from authorized and unissued

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Common Stock or Common Stock held in or hereafter acquired for the treasury of
the Company. If any outstanding Option granted under the Plan expires, lapses or
is terminated for any reason, the Option Shares allocable to the unexercised
portion of such Option may again by the subject of an Option granted pursuant to
the Plan. The maximum number of shares of the Common Stock for which Options may
be issued to any single employee of the Company or its Affiliates in any
calendar year, adjusted as provided in Section 9, shall be, in 1994, 2,300,000
shares, and thereafter 500,000 shares.

          5. Term of Plan. The Plan is effective as of January 5, 1987. No
Option may be granted under the Plan after January 4, 1997.

          6. Terms and Conditions of Options. Options granted pursuant to the
Plan shall be evidenced by written documents (the "Option Documents") in such
form as the Committee shall from time to time approve, which Option Documents
shall comply with and be subject to the following terms and conditions and such
other terms and conditions which the Committee shall from time to time require
which are not inconsistent with the terms of the Plan. However, the provisions
of this Section 6 shall not be applicable to Options granted to non-employee
directors, except as otherwise provided in subsection 8(c).

               (a) Number of Option Shares. Each Option Document shall state the
number of Option Shares to which it pertains. Notwithstanding that any such
Option is intended to be an ISO, such option shall not be an ISO to the extent
that it would not be so treated under the rules contained in Section 422(d) of
the Code, and the Regulations thereunder (dealing with the annual vesting
limit).

               (b) Option Price. Each Option Document shall state the price at
which Option Shares may be purchased (the "Option Price"), which shall be at
least 100% of the fair market value of the Common Stock at the time the Option
is granted as determined by the Committee; provided, however, that if an ISO is
granted to an Optionee who then owns, directly or by attribution under Section
424(d) of the Code, shares possessing more than ten percent of the total
combined voting power of all classes of stock of the Company or an Affiliate,
then the Option Price shall be at least 110% of the fair market value of the
Option Shares at the time the Option is granted.

               (c) Medium of Payment. An Optionee shall pay for Option Shares
(i) in cash, (ii) by certified check payable to the order of the company, or
(iii) by a combination of the foregoing. In addition, the Committee may provide
in an Option Document that payment may be made all or in part in Other Available
Shares held by the Optionee (a) in the case of payment for ISOs outstanding as
of March 28, 1990, for more than one year, or (b) in the case of payment for all
other Options (unless otherwise provided in an Option Document), for more than
six months or such shorter period of time as shall not, in the Committee's sole
discretion, have an adverse effect on the Company's financial statements;
provided, however, that Option Shares may not be

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paid for in shares of Class A Common Stock if such method of payment would
result in liability under Section 16(b) of the Securities Exchange Act of 1934
to an Optionee. Except as otherwise provided by the Committee, if payment is
made in whole or in part in shares of the Common Stock or Class A Common Stock
of the Company, then the Optionee shall deliver to the Company certificates
registered in the name of such Optionee representing shares of Common Stock or
Class A Common Stock legally and beneficially owned by such Optionee, free of
all liens, claims and encumbrances of every kind and having a fair market value
on the date of delivery that is not greater than the Option Price of the Option
Shares with respect to which such Option is to be exercised, accompanied by
stock powers duly endorsed in blank by the record holder of the shares
represented by such certificates. Notwithstanding the foregoing, the Committee,
in its sole discretion, may refuse to accept shares of Common Stock or Class A
Common Stock in payment of the Option Price. In that event, any certificates
representing shares of Common Stock or Class A Common Stock which were delivered
to the Company shall be returned to the Optionee with notice of the refusal of
the Committee to accept such shares in payment of the Option Price. The
Committee may impose such limitations and prohibitions on the use of shares of
the Common Stock or Class A Common Stock to exercise an Option as it deems
appropriate.

               (d) Termination of Options. No Option shall be exercisable after
the first to occur of the following:

                    (i) Expiration of the Option term specified in the Option
Document, which for an ISO, shall not exceed (A) ten years from the date of
grant, or (B) five years from the date of grant if the Optionee on the date of
grant owns, directly or by attribution under Section 424(d) of the Code, shares
possessing more than ten percent of the total combined voting power of all
classes of stock of the Company or of an Affiliate, and which for any other
Option shall not exceed ten years and six months from the date of grant;

                    (ii) Expiration of three months from the date the Optionee's
employment with the Company or its Affiliates terminates for any reason other
than disability (within the meaning of Section 22(e)(3) of the Code)
("Disability"), death or as specified in subsection 6(d)(iv) or (v) below,
provided, however, that the Committee may specify in an Option Document that an
Option may be exercisable during a longer period following the date the
Optionee's employment with the Company or its Affiliates so terminates, but in
no event later than the expiration of the Option Term specified in such Option
Document;

                    (iii) Expiration of one year from the date the Optionee's
employment with the Company or its Affiliates terminates by reason of the
Optionee's Disability or death;

                    (iv) The date set by the Committee pursuant to Section 13 in
connection with a Terminating Event; or

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                    (v) A finding by the Committee, after full consideration of
the facts presented on behalf of both the Company and the Optionee, that the
Optionee has breached his employment contract with the Company or an Affiliate,
or has been engaged in any sort of disloyalty to the Company or an Affiliate,
including, without limitation, fraud, embezzlement, theft, commission of a
felony or proven dishonesty in the course of his employment or has disclosed
trade secrets of the Company or an Affiliate. In such event, in addition to
immediate termination of the Option, the Optionee, upon a determination by the
Committee shall automatically forfeit all Option Shares for which the Company
has not yet delivered the share certificates upon refund by the Company of the
Option Price.

               (e) Transfers. This subsection 6(e) shall not apply to Options
described in Section 6.1.

                    (i) In General. Except as provided in subsection 6(e)(ii),
no Option granted under the Plan may be transferred, except by will or by the
laws of descent and distribution. During the lifetime of the person to whom an
Option is granted, such Option may be exercised only by him.

                    (ii) Transferable Options. The Committee may, in its
discretion, at the time of grant of an Option that is not an ISO (an "NQO") or
by amendment of an Option Document for an ISO or an NQO, provide that Options
granted to or held by an Optionee may be transferred, in whole or in part, to
one or more transferees and exercised by any such transferee; provided further
that (A) any such transfer is without consideration and (B) each transferee is a
member of such Optionee's Immediate Family (as hereinafter defined); and
provided further that any ISO granted pursuant to an Option Document which is
amended to permit transfers during the lifetime of the Optionee shall, upon the
effectiveness of such amendment, be treated thereafter as an NQO. No transfer of
an Option shall be effective unless the Committee is notified of the terms and
conditions of the transfer and the Committee determines that the transfer
complies with the requirements for transfers of Options under the Plan and the
Option Document. Any person to whom an Option has been transferred may exercise
any Options only in accordance with the provisions of subsections 6(c), 6(d),
6(f) and this subsection 6(e). For purposes of this subsection 6(e), the term
"Immediate Family" shall mean an Optionee's spouse and lineal descendants, any
trust all beneficiaries of which are any of such persons and any partnership all
partners of which are any of such persons.

               (f) Other Provisions. The Option Documents shall contain such
other provisions including, without limitation, additional restrictions upon the
exercise of the Option or additional limitations upon the term of the Option, as
the Committee shall deem advisable.

               (g) Amendment. The Committee shall have the right to amend Option
Documents issued to an Optionee subject to his consent, except that the consent
of the Optionee shall not be required for any amendment made under subsection
6(d)(iv).

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               (h) Exercisability. To the extent that the grant of an Option
would be subject to Section 16(b) of the Securities Exchange Act of 1934 unless
the requirements for exemption therefrom in Rule 16b-3(c)(1), under such Act, or
any successor provision, are met, the Option Documents shall provide that such
Option is not exercisable until not less than six months have elapsed from the
date of grant.

          6.1 Certain Options Awarded to Ralph J. Roberts. With respect to those
Options awarded to Ralph J. Roberts on January 8, 1992 (options to purchase
249,441 shares of Class A Special Common Stock at $16.25 per share), and January
6, 1993 (options to purchase 249,545 shares of Class A Special Common Stock at
$18.125 per share), and notwithstanding subsection 6(e) of this Plan, the
Committee may, in its discretion, amend such Options to provide that such
Options may be transferred by Mr. Roberts, in whole or in part, to one or more
transferees and exercised by any such transferee, provided that (i) any such
transfer is without consideration, and (ii) each transferee is a member of Mr.
Roberts' Immediate Family. "Immediate Family" shall mean Mr. Roberts' spouse,
children, grandchildren, any trust all beneficiaries of which are such persons,
and any partnership all partners of which are such persons. In the event the
Committee so amends such Options, the Committee shall include in such amended
Options such further provisions as it determines are necessary or appropriate at
the time of such amendment to permit the Company to deduct compensation expenses
recognized upon exercise of such options for federal or state income tax
purposes.

          7. Exercise. No Option shall be deemed to have been exercised prior to
the receipt by the Company of written notice of such exercise and of payment in
full of the Option Price for the Option Shares to be purchased. Each such notice
shall specify the number of Option Shares to be purchased and shall (unless the
Option Shares are covered by a then current registration statement or a
Notification under Regulation A under the Securities Act of 1933 (the "Act")),
contain the Optionee's acknowledgment in form and substance satisfactory to the
Company that (2) such Option Shares are being purchased for investment and not
for distribution or resale (other than a distribution or resale which, in the
opinion of counsel satisfactory to the Company, may be made without violating
the registration provisions of the Act), (b) the Optionee has been advised and
understands that (i) the Option Shares have not be registered under the Act and
are "restricted securities" within the meaning of Rule 144 under the Act and are
subject to restrictions on transfer and (ii) the Company is under no obligation
to register the Option Shares under the Act or to take any action which would
make available to the Optionee any exemption from such registration, and (c)
such Option Shares may not be transferred without compliance with all applicable
federal and state securities laws. Notwithstanding the above, should the Company
be advised by counsel that issuance of shares should be delayed pending (A)
registration under federal or state securities laws or (B) the receipt of an
opinion that an appropriate exemption therefrom is available, the Company may
defer exercise of any Option granted hereunder until either such event in (A) or
(B) has occurred.


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          8. Special Provisions Relating to Grants of Options to Non-employee
Directors. Options granted pursuant to the Plan to non-employee directors shall
be granted, without any further action by the Committee, in accordance with the
terms and conditions set forth in this Section 8. Options granted pursuant to
this Section 8 shall be evidenced by Option Documents in such form as the
Committee shall from time to time approve, which Option Documents shall comply
with and be subject to the following terms and conditions and such other terms
and conditions as the Committee shall from time to time require which are not
inconsistent with the terms of the Plan.

               (a) Timing of Grants; Number of Shares Subject of Options;
Exercisability of Options; Option Price. Each non-employee director shall be
granted, commencing on February 1, 1995 and on each successive February 1 (the
"Grant Date") thereafter, an Option to purchase five thousand four hundred
(5,400) shares of Common Stock. Notwithstanding anything herein to the contrary,
each newly elected non-employee director who is first elected to the Board of
Directors after February 1, 1994 shall (i) be granted an Option to purchase nine
thousand (9,000) shares of Common Stock on the date on which such non-employee
director is elected to the Board of Directors (the "Election Date") and (ii) not
be entitled to the grant of an Option hereunder on the Grant Date immediately
following the non-employee director's Election Date if such Election Date is
within ninety (90) days of the Grant Date. No such Option shall be an ISO, and
each such Option shall first become exercisable six months after the date of
grant and shall then be exercisable in its entirety. The Option Price shall be
equal to 100% of the fair market value of the Common Stock on the date the
Option is granted.

               (b) Termination of Options Granted Pursuant to Section 8.

                    (i) All options granted pursuant to this Section 8 shall be
exercisable until the first to occur of the following:

                         (A) Expiration of five (5) years from the date of
     grant;

                         (B) Expiration of ninety (90) days from the date the
     Optionee's service as a non-employee director terminates for any reason
     other than Disability or death or as otherwise specified in subsection
     8(b)(i)(D) below;

                         (C) Expiration of one (1) year from the date the
     Optionee's service with Company as a non-employee director terminates due
     to the Optionee's Disability or death; or

                         (D) The date the Optionee's directorship is terminated,
     if the directorship is terminated on account of (1) any act of fraud,
     intentional misrepresentation, embezzlement or theft, (2) commission of a
     felony or (3) disclosure of

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<PAGE>

     trade secrets of the Company or an Affiliate. In such event, in addition to
     the immediate termination of the Option, the Optionee shall automatically
     forfeit all Option Shares for which the Company has not yet delivered the
     share certificates upon refund by the Company of the Option Price.

               (c) Applicability of Certain Provisions of Section 6 to Options
Granted Pursuant to Section 8. The following provisions of Section 6 shall be
applicable to Options granted pursuant to this Section 8: Subsection 6(a)
(provided that no Option granted pursuant to this Section 8 shall be an ISO);
subsection 6(c) (provided that Option Documents relating to options granted
pursuant to this Section 8 shall provide that payment may be made in whole or
part in shares of Common Stock or Class A Common Stock held by the Optionee for
more than six months, subject to the limitation on payment in shares of Class A
Common Stock set forth in subsection 6(c) if such method of payment would result
in liability under Section 16(b) of the Securities Exchange Act of 1934);
subsection 6(e); subsection 6(g); and subsection 6(h).

          9. Adjustments on Changes in Capitalization. The aggregate number of
shares and class of shares as to which Options may be granted hereunder, the
number of shares covered by each outstanding Option, and the Option Price
thereof shall be appropriately adjusted in the event of a stock dividend, stock
split, recapitalization or other change in the number or class of issued and
outstanding equity securities of the Company resulting from a subdivision or
consolidation of the Common Stock and/or other outstanding equity security or a
recapitalization or other capital adjustment (not including the issuance of
Common Stock on the conversion of other securities of the Company which are
convertible into Common Stock) affecting the Common Stock which is effected
without receipt of consideration by the Company. The Committee shall have
authority to determine the adjustments to be made under this Section and any
such determination by the Committee shall be final, binding and conclusive;
provided, however, that no adjustment shall be made which will cause an ISO to
lose its status as such without the consent of the Optionee and no adjustment
shall be made to the number of shares set forth in subsection 8(a). However, an
Option granted pursuant to subsection 8(a). However, an Option granted pursuant
to subsection 8(a) shall be subject to adjustment in accordance with the
provisions of this Section 9 after the date of grant.

          10. Amendment of the Plan. The Board or the Committee may amend the
Plan from time to time in such manner as it may deem advisable. Nevertheless,
neither the Board nor the Committee may, without within twelve months before or
after such action obtaining approval by such vote of shareholders as may be
required by Pennsylvania law for any action requiring shareholder approval, or
by a majority of votes cast at a duly held shareholders' meeting at which a
majority of all voting stock is present and voting on such amendment, either in
person or in proxy (but not, in any event, less than the vote required pursuant
to Rule 16b-3(b) under the Securities Exchange Act of 1934), change the class of
individuals eligible to receive an ISO, extend the expiration date of the Plan,
decrease the minimum Option Price of an ISO granted under the Plan or increase
the maximum number of shares as to which Options may be granted,

                                       -8-

<PAGE>

except as provided in Section 9 hereof. In addition, the provisions of Section 8
that determine (i) which directors shall be granted Options pursuant to Section
8; (ii) the number of Option Shares subject to Options granted pursuant to
Section 8; (iii) the Option Price of Option Shares subject to Options granted
pursuant to Section 8; and (iv) the timing of grants of Options pursuant to
Section 8 shall not be amended more than once every six months, other than to
comport with changes in the Code or the Employee Retirement Income Security Act
of 1974, as amended, if applicable.

          11. Continued Employment. The grant of an Option pursuant to the Plan
shall not be construed to imply or to constitute evidence of any agreement,
express or implied, on the part of the Company or any Affiliate to retain the
Optionee in the employ of the Company or an Affiliate or as a member of the
Company's Board of Directors or in any other capacity.

          12. Withholding of Taxes.

               (a) Whenever the Company proposes or is required to deliver or
transfer Option Shares in connection with the exercise of an Option, the Company
shall have the right to (i) require the recipient to remit to the Company an
amount sufficient to satisfy any federal, state and/or local withholding tax
requirements prior to the delivery or transfer of any certificate or
certificates for such Option Shares or (ii) take any action whatever that it
deems necessary to protect its interests with respect to tax liabilities. The
Company's obligation to make any delivery or transfer of Option Shares shall be
conditioned on the recipient's compliance, to the Company's satisfaction, with
any withholding requirement.

               (b) Except as otherwise provided in this Section 12(b), any tax
liabilities incurred in connection with the exercise of an Option under the Plan
other than an ISO shall be satisfied by the Company's withholding a portion of
the Option Shares underlying the Option exercised having a fair market value
approximately equal to the minimum amount of taxes required to be withheld by
the Company under applicable law, unless otherwise determined by the Committee
with respect to any participant. Notwithstanding the foregoing, the Committee
may permit an Optionee to elect one or both of the following: (i) to have taxes
withheld in excess of the minimum amount required to be withheld by the Company
under applicable law; provided that the Optionee certifies in writing to the
Company that the Optionee owns a number of Other Available Shares that is at
least equal to the number to be withheld by the Company for the then-current
exercise on account of withheld taxes in excess of such minimum amount, and (ii)
to pay to the Company in cash all or a portion of the taxes to be withheld upon
the exercise of an Option. In all cases, the Option Shares so withheld by the
Company shall have a fair market value that does not exceed the amount of taxes
to be withheld minus the cash payment, if any, made by the Optionee. The fair
market value of such shares shall be determined based on the last reported sale
price of a share of Common Stock on the principal exchange on which the Common
Stock is listed or, if not so listed, on the Nasdaq Stock Market on the last
trading day prior to the date on which the Option is exercised. Any election
pursuant to this Section 12(b) must be in

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<PAGE>

writing made prior to the date specified by the Committee, and in any event
prior to the date the amount of tax to be withheld or paid is determined. In
addition, with respect to persons subject to reporting requirements under
Section 16(a) of the 1934 Act, such election must be made at least six months
prior to the date the amount of tax to be withheld or paid is determined (which
election will remain in effect with regard to the exercise of an Option and all
future exercises of Options unless revoked upon six months prior notice). An
election pursuant to this Section may be made only by an Optionee or, in the
event of the Optionee's death, by the Optionee's legal representative. No shares
withheld pursuant to this Section 12(b) shall be available for subsequent grants
under the Plan. The Committee may add such other requirements and limitations
regarding elections pursuant to this Section 12(b) as it deems appropriate.

          13. Terminating Events.

               (a) The Sponsor shall give Optionees at least thirty (30) days'
notice (or, if not practicable, such shorter notice as may be reasonably
practicable) prior to the anticipated date of the consummation of a Terminating
Event. Upon receipt of such notice, and for a period of ten (10) days thereafter
(or such shorter period as the Board shall reasonably determine and so notify
the Optionees), each Optionee shall be permitted to exercise the Option to the
extent the Option are then exercisable; provided that, the Sponsor may, by
similar notice, require the Optionee to exercise the Option, to the extent the
Option is then exercisable, or to forfeit the Option (or portion thereof, as
applicable). The Committee may, in its discretion, provide that upon the
Optionee's receipt of the notice of a Terminating Event under this Section
13(a), the entire number of Shares covered by Options shall become immediately
exercisable. Upon the close of the period described in this Section 13(a) during
which an Option may be exercised in connection with a Terminating Event, such
Option (including such portion thereof that is not exercisable) shall terminate
to the extent that such Option have not theretofore been exercised.

               (b) Notwithstanding Section 13(a), in the event the Terminating
Event is not consummated, the Option shall be deemed not to have been exercised
and shall be exercisable thereafter to the extent it would have been exercisable
if no such notice had been given.

          14. Additional Definitions.

               (a) "Affiliate." For purposes of this Section 14, "Affiliate"
means, with respect to any Person, any other Person that, directly or
indirectly, is in control of, is controlled by, or is under common control with,
such Person. For purposes of this definition, the term "control," including its
correlative terms "controlled by" and "under common control with," mean, with
respect to any Person, the possession, directly or indirectly, of the power to
direct or cause the direction of the management and policies of such Person,
whether through the ownership of voting securities, by contract or otherwise.

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<PAGE>

               (b) "Board" means the board of directors of the Sponsor.

               (c) "Change of Control" means any transaction or series of
transactions as a result of which any Person who was a Third Party immediately
before such transaction or series of transactions owns then-outstanding
securities of the Sponsor having more than 50 percent of the voting power for
the election of directors of the Sponsor.

               (d) "Comcast Plan" means any restricted stock, stock bonus, stock
option or other compensation plan, program or arrangement established or
maintained by the Company or an Affiliate, including but not limited to this
Plan, the Comcast Corporation 1996 Stock Option Plan and the 1990 Restricted
Stock Plan.

               (e) "Common Stock." For purposes of the definition of the term
"Other Available Shares" in Section 12(f), "Common Stock" means:

                              (i)       the Sponsor's Class A Common Stock, par
                                        value, $1.00 per share; and

                              (ii)      the Sponsor's Class A Special Common
                                        Stock, par value, $1.00 per share

               (f) "Other Available Shares" means, as of any date, the excess,
if any of:

                    (i) the total number of shares of Common Stock owned by an
Optionee; over

                    (ii) the sum of:

                              (x)       the number of shares of Common Stock
                                        owned by such Optionee for less than six
                                        months; plus

                              (y)       the number of shares of Common Stock
                                        owned by such Optionee that has, within
                                        the preceding six months, been the
                                        subject of a withholding certification
                                        pursuant to Section 12(b) or any similar
                                        withholding certification under any
                                        other Comcast Plan; plus

                              (z)       the number of shares of Common Stock
                                        owned by such Optionee that has, within
                                        the preceding six months, been received
                                        in exchange for Shares

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<PAGE>

                                        surrendered as payment, in full or in
                                        part, of the exercise price for an
                                        option to purchase any securities of the
                                        Sponsor or an Affiliate under any
                                        Comcast Plan, but only to the extent of
                                        the number of Shares surrendered.

For purposes of Section 6(c), the number of Other Available Shares shall be
determined separately for the Company's Class A Special Common Stock, par value,
$1.00 per share, and for the Company's Class A Common Stock, par value, $1.00
per share.

               (g) "Person" means an individual, a corporation, a partnership,
an association, a trust or any other entity or organization.

               (h) "Roberts Family." Each of the following is a member of the
Roberts Family:

                    (i) Ralph J. Roberts;

                    (ii) a lineal descendant of Ralph J. Roberts; or

                    (iii) a trust established for the benefit of any of Ralph J.
Roberts and/or a lineal descendant or descendants of Ralph J. Roberts.

               (i) "Sponsor" means Comcast Corporation, a Pennsylvania
corporation, including any successor thereto by merger, consolidation,
acquisition of all or substantially all the assets thereof, or otherwise.

               (j) "Terminating Event" means any of the following events:

                    (i) the liquidation of the Sponsor; or

                    (ii) a Change of Control.


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<PAGE>

               (k) "Third Party" means any Person other than a Company, together
with such Person's Affiliates, provided that the term "Third Party" shall not
include the Sponsor, an Affiliate of the Sponsor or any member or members of the
Roberts Family.

                        Executed as of the 10th day of December, 1996


                                      COMCAST CORPORATION

                                      BY: /s/ Stanley Wang

                                      ATTEST: /s/ Arthur R. Block




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