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                                                                   EXHIBIT 10.39


                         REGISTRATION RIGHTS AGREEMENT



     THIS REGISTRATION RIGHTS AGREEMENT is made and entered into as of December
28, 1998 by and between At Home Corporation, a Delaware corporation ("the
Company"), and Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith
Incorporated, Morgan Stanley & Co. Incorporated and Goldman, Sachs & Co. (the
"Purchasers") pursuant to the Purchase Agreement, dated as of December 28, 1998
(the "Purchase Agreement"), between the Company and the Purchasers.  In order to
induce the Purchasers to enter into the Purchase Agreement, the Company has
agreed to provide the registration rights set forth in this Agreement.  The
execution of this Agreement is a condition to the closing under the Purchase
Agreement.

     The Company agrees with the Purchasers, (i) for their benefit as Purchasers
and (ii) for the benefit of the beneficial owners (including the Purchasers)
from time to time of the Debentures (as defined herein) and the beneficial
owners from time to time of the Underlying Common Stock (as defined herein)
issued upon conversion of the Debentures (each of the foregoing a "Holder" and
together the "Holders"), as follows:

     Section 1.  Definitions. Capitalized terms used herein without definition
shall have their respective meanings set forth in the Purchase Agreement. As
used in this Agreement, the following terms shall have the following meanings:

     Affiliate:  With respect to any specified person, an "affiliate," as
defined in Rule 144, of such person.

     Amendment Effectiveness Deadline Date:  See Section 2(d) hereof.

     Applicable Conversion Price:  The Applicable Conversion Price as of any
date of determination means the Applicable Principal Amount per $1,000 principal
amount at maturity of Debentures as of such date of determination divided by the
Conversion Rate in effect as of such date of determination or, if no Debentures
are then outstanding, the Conversion Rate that would be in effect were
Debentures then outstanding.

     Applicable Principal Amount:  Applicable Principal Amount as of any date of
determination, with respect to each $1,000 principal amount at maturity of
Debentures means the sum of the initial issue price of such Debenture ($524.64)
plus accrued original issue discount with respect to such Debenture through such
date of determination or, if no Debentures are then outstanding, such sum
calculated as if such Debentures were then outstanding.

     Business Day:  Each Monday, Tuesday, Wednesday, Thursday and Friday that is
not a day on which banking institutions in The City of New York are authorized
or obligated by law or

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executive order to close.

     Common Stock:  The shares of Series A Common Stock, $0.01 par value, of the
Company and any other shares of common stock as may constitute "Series A Common
Stock" for purposes of the Indenture, including the Underlying Common Stock.

     Conversion Rate: Conversion Rate shall have the meaning assigned such term
in the Indenture.

     Damages Accrual Period:  See Section 2(e) hereof.

     Damages Payment Date:  Each June 28 and December 28 in the case of
Debentures and the Underlying Common Stock.

     Debentures:   The Convertible Subordinated Debentures due 2018 of the
Company to be purchased pursuant to the Purchase Agreement.

     Deferral Notice: See Section 3(i) hereof.

     Deferral Period:  See Section 3(i) hereof.

     Effectiveness Deadline Date:  See Section 2(a) hereof.

     Effectiveness Period:  The period of two years from the later of the (a)
Issue Date or (b) the last date of original issuance of the Debentures or such
shorter period ending on the date that all Registrable Securities have ceased to
be Registrable Securities.

     Event:  See Section 2(e) hereof.

     Event Termination Date:  See Section 2(e) hereof.

     Event Date:  See Section 2(e) hereof.

     Exchange Act:  The Securities Exchange Act of 1934, as amended, and the
rules and regulations of the SEC promulgated thereunder.

     Filing Deadline Date:  See Section 2(a) hereof.

     Holder:  See the second paragraph of this Agreement.

     Indenture:  The Indenture dated as of the date hereof between the Company
and State Street Bank and Trust Company of California, N.A., as trustee,
pursuant to which the Debentures are being issued.

     Initial Shelf Registration Statement:  See Section 2(a) hereof.

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     Issue Date:  December 28, 1998.

     Liquidated Damages Amount:  See Section 2(e) hereof.

     Losses:  See Section 6 hereof.

     Material Event: See Section 3(i) hereof.

     Notice and Questionnaire:  A written notice delivered to the Company
containing substantially the information called for by the Selling Security
holder Notice and Questionnaire attached as Appendix B to the Offering
Memorandum of the Company issued December 21, 1998 relating to the Debentures.

     Notice Holder:  On any date, any Holder that has delivered a Notice and
Questionnaire to the Company on or prior to such date.

     Prospectus:  The prospectus included in any Registration Statement
(including, without limitation, a prospectus that discloses information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 430A promulgated under the Securities Act), as
amended or supplemented by any amendment or prospectus supplement, including
post-effective amendments, and all materials incorporated by reference or
explicitly deemed to be incorporated by reference in such Prospectus.

     Purchase Agreement:  See the first paragraph of this Agreement.

     Purchasers:  Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith
Incorporated, Morgan Stanley & Co. Incorporated and Goldman, Sachs & Co.

     Record Holder:  With respect to any Damages Payment Date relating to any
Debenture or Underlying Common Stock as to which any Liquidated Damages Amount
has accrued, the registered holder of such Debenture or Underlying Common Stock,
as the case may be, 15 days prior to the next succeeding Damages Payment Date.

     Registrable Securities:  The Debentures and the Underlying Common Stock,
until such securities have been converted or exchanged, and, at all times
subsequent to any such conversion or exchange, any securities into or for which
such securities have been converted or exchanged, and any security issued with
respect thereto upon any stock dividend, split or similar event until, in the
case of any such security, the earliest of (i) its effective registration under
the Securities Act and resale in accordance with the Registration Statement
covering it, (ii) expiration of the holding period that would be applicable
thereto under Rule 144(k) were it not held by an Affiliate of the Company or
(iii) its sale to the public pursuant to Rule 144.

     Registration Expenses:  See Section 5 hereof.

     Registration Statement:  Any registration statement of the Company that
covers any of 

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the Registrable Securities pursuant to the provisions of this Agreement,
including the Prospectus, amendments and supplements to such registration
statement, including post-effective amendments, all exhibits, and all materials
incorporated by reference or explicitly deemed to be incorporated by reference
in such registration statement.

     Restricted Securities:  As this term is defined in Rule 144.

     Rule 144:  Rule 144 under the Securities Act, as such Rule may be amended
from time to time, or any similar rule or regulation hereafter adopted by the
SEC.

     Rule 144A:  Rule 144A under the Securities Act, as such Rule may be amended
from time to time, or any similar rule or regulation hereafter adopted by the
SEC.

     SEC:  The Securities and Exchange Commission.

     Securities Act:  The Securities Act of 1933, as amended, and the rules and
regulations promulgated by the SEC thereunder.

     Shelf Registration Statement:  See Section 2(a) hereof.

     Subsequent Shelf Registration Statement:  See Section 2(b) hereof.

     TIA:  The Trust Indenture Act of 1939, as amended.

     Trustee:  State Street Bank and Trust Company of California, N.A. (or any
successor entity), the Trustee under the Indenture.

     Underlying Common Stock:  The Series A Common Stock into which the
Debentures are convertible or issued upon any such conversion.

     Section 2.  Shelf Registration.  (a)  The Company shall prepare and file or
cause to be prepared and filed with the SEC, as soon as practicable but in any
event by the date (the "Filing Deadline Date") ninety (90) days after the Issue
Date, a Registration Statement for an offering to be made on a delayed or
continuous basis pursuant to Rule 415 of the Securities Act (a "Shelf
Registration Statement") registering the resale from time to time by Holders
thereof of all of the Registrable Securities (the "Initial Shelf Registration
Statement"). The Initial Shelf Registration Statement shall be on Form S-3 or
another appropriate form permitting registration of such Registrable Securities
for resale by such Holders in accordance with the methods of distribution
elected by the Holders and set forth in the Initial Shelf Registration
Statement. The Company shall use all reasonable efforts to cause the Initial
Shelf Registration Statement to be declared effective under the Securities Act
as promptly as is practicable but in any event by the date (the "Effectiveness
Deadline Date") that is one hundred and eighty (180) days after the Issue Date,
and to keep the Initial Shelf Registration Statement (or any Subsequent Shelf
Registration Statement) continuously effective under the Securities Act until
the expiration of the Effectiveness Period. At the time the Initial Shelf
Registration Statement is declared effective, 

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each Holder that became a Notice Holder on or prior to the date 10 Business Days
prior to such time of effectiveness shall be named as a selling Security holder
in the Initial Shelf Registration Statement and the related Prospectus in such a
manner as to permit such Holder to deliver such Prospectus to purchasers of
Registrable Securities in accordance with applicable law. None of the Company's
security holders (other than the Holders of Registrable Securities) shall have
the right to include any of the Company's securities in the Shelf Registration
Statement.

       (b)  If the Initial Shelf Registration Statement or any Subsequent Shelf
Registration Statement ceases to be effective for any reason at any time during
the Effectiveness Period (other than because all Registrable Securities
registered thereunder shall have been resold pursuant thereto or shall have
ceased to be Registrable Securities), the Company shall use all reasonable
efforts to obtain the prompt withdrawal of any order suspending the
effectiveness thereof, and in any event shall within thirty (30) days of such
cessation of effectiveness amend the Shelf Registration Statement in a manner
reasonably expected to obtain the withdrawal of the order suspending the
effectiveness thereof, or file an additional Shelf Registration Statement
covering all of the securities that as of the date of such filing are
Registrable Securities (a "Subsequent Shelf Registration Statement").  If a
Subsequent Shelf Registration Statement is filed, the Company shall use all
reasonable efforts to cause the Subsequent Shelf Registration Statement to
become effective as promptly as is practicable after such filing and to keep
such Registration Statement (or subsequent Shelf Registration Statement)
continuously effective until the end of the Effectiveness Period.

       (c)  The Company shall supplement and amend the Shelf Registration
Statement if required by the rules, regulations or instructions applicable to
the registration form used by the Company for such Shelf Registration Statement,
if required by the Securities Act or, to the extent to which the Company does
not reasonably object, as reasonably requested by the Purchasers or by the
Trustee on behalf of the registered Holders.

       (d)  Each Holder of Registrable Securities agrees that if such Holder
wishes to sell Registrable Securities pursuant to a Shelf Registration Statement
and related Prospectus, it will do so only in accordance with this Section 2(d)
and Section 3(i).  Each Holder of Registrable Securities wishing to sell
Registrable Securities pursuant to a Shelf Registration Statement and related
Prospectus agrees to deliver a Notice and Questionnaire to the Company at least
three (3) Business Days prior to any intended distribution of Registrable
Securities under the Shelf Registration Statement.  From and after the date the
Initial Shelf Registration Statement is declared effective, the Company shall,
as promptly as is practicable after the date a Notice and Questionnaire is
delivered, and in any event within five (5) Business Days after such date, (i)
if required by applicable law, file with the SEC a post-effective amendment to
the Shelf Registration Statement or prepare and, if required by applicable law,
file a supplement to the related Prospectus or a supplement or amendment to any
document incorporated therein by reference or file any other required document
so that the Holder delivering such Notice and Questionnaire is named as a
selling Security holder in the Shelf Registration Statement and the related
Prospectus in such a manner as to permit such Holder to deliver such Prospectus
to 

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<PAGE>
 
purchasers of the Registrable Securities in accordance with applicable law
and, if the Company shall file a post-effective amendment to the Shelf
Registration Statement, use all reasonable efforts to cause such post-effective
amendment to be declared effective under the Securities Act as promptly as is
practicable, but in any event by the date (the "Amendment Effectiveness Deadline
Date") that is forty-five (45) days after the date such post-effective amendment
is required by this clause to be filed; (ii) provide such Holder copies of any
documents filed pursuant to Section 2(d)(i); and (iii) notify such Holder as
promptly as practicable after the effectiveness under the Securities Act of any
post-effective amendment filed pursuant to Section 2(d)(i); provided, that if
such Notice and Questionnaire is delivered during a Deferral Period, the Company
shall so inform the Holder delivering such Notice and Questionnaire and shall
take the actions set forth in clauses (i), (ii) and (iii) above upon expiration
of the Deferral Period in accordance with Section 3(i), provided, further, that
if under applicable law the Company has more than one option as to the type or
manner of making any such filing, it will make the required filing or filings in
the manner or of a type that is reasonably expected to result in the earliest
availability of the Prospectus for effecting resales of Registrable Securities.
Notwithstanding anything contained herein to the contrary, the Company shall be
under no obligation to name any Holder that is not a Notice Holder as a selling
Security holder in any Registration Statement or related Prospectus; provided,
however, that any Holder that becomes a Notice Holder pursuant to the provisions
of Section 2(d) of this Agreement (whether or not such Holder was a Notice
Holder at the time the Registration Statement was declared effective) shall be
named as a selling Security holder in the Registration Statement or related
Prospectus in accordance with the requirements of this Section 2(d).

       (e)  The parties hereto agree that the Holders of Registrable Securities
will suffer damages, and that it would not be feasible to ascertain the extent
of such damages with precision, if (i) the Initial Shelf Registration Statement
has not been filed on or prior to the Filing Deadline Date, (ii) the Initial
Shelf Registration Statement has not been declared effective under the
Securities Act on or prior to the Effectiveness Deadline Date, (iii) the Company
has failed to perform its obligations set forth in Section 2(d) within the time
period required therein, (iv) the aggregate duration of Deferral Periods in any
period exceeds the number of days permitted in respect of such period pursuant
to Section 3(i) hereof or (v) the number of Deferral Periods in any period
exceeds the number permitted in respect of such period pursuant to Section 3(i)
(each of the events of a type described in any of the foregoing clauses (i)
through (v) are individually referred to herein as an "Event," and the Filing
Deadline Date in the case of clause (i), the Effectiveness Deadline Date in the
case of clause (ii), the date by which the Company is required to perform its
obligations set forth in Section 2(d) in the case of clause (iii) (including the
filing of any post-effective amendment prior to the Amendment Effectiveness
Deadline Date), the date on which the aggregate duration of Deferral Periods in
any period exceeds the number of days permitted by Section 3(i) hereof in the
case of clause (iv), and the date of the commencement of a Deferral Period that
causes the limit on the number of Deferral Periods in any period under Section
3(i) hereof to be exceeded in the case of clause (v), being referred to herein
as an "Event Date").  Events shall be deemed to continue until the "Event
Termination Date," which shall be the following dates with respect to the
respective types of Events:  the date the Initial Shelf 

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Registration Statement is filed in the case of an Event of the type described in
clause (i), the date the Initial Shelf Registration Statement is declared
effective under the Securities Act in the case of an Event of the type described
in clause (ii), the date the Company performs its obligations set forth in
Section 2(d) in the case of an Event of the type described in clause (iii)
(including, without limitation, the date the relevant post-effective amendment
to the Shelf Registration Statement is declared effective under the Securities
Act), termination of the Deferral Period that caused the limit on the aggregate
duration of Deferral Periods in a period set forth in Section 3(i) to be
exceeded in the case of the commencement of an Event of the type described in
clause (iv), and termination of the Deferral Period the commencement of which
caused the number of Deferral Periods in a period permitted by Section 3(i) to
be exceeded in the case of an Event of the type described in clause (v).

     Accordingly, commencing on (and including) any Event Date and ending on
(but excluding) the next date on which there are no Events that have occurred
and are continuing (a "Damages Accrual Period"), the Company agrees to pay, as
liquidated damages and not as a penalty, an amount (the "Liquidated Damages
Amount"), payable on the Damages Payment Dates to Record Holders of then
outstanding Debentures that are Registrable Securities and of then outstanding
shares of Underlying Common Stock issued upon conversion of Debentures that are
Registrable Securities, as the case may be, accruing, for each portion of such
Damages Accrual Period beginning on and including a Damages Payment Date (or, in
respect of the first time that the Liquidation Damages Amount is to be paid to
Holders on a Damages Payment Date as a result of the occurrence of any
particular Event, from the Event Date) and ending on but excluding the first to
occur of (A) the date of the end of the Damages Accrual Period or (B) the Next
Damages Payment Date, at a rate per annum equal to one-quarter of one percent
(.25%) for the first 90-day period from the Event Date and thereafter at a rate
per annum equal to one-half of one percent (.5%) of the aggregate Applicable
Principal Amount of such Debentures and the Applicable Conversion Price of such
shares of Underlying Common Stock, as the case may be, in each case determined
as of the Business Day immediately preceding the next Damages Payment Date;
provided, that in the case of a Damages Accrual Period that is in effect solely
as a result of an Event of the type described in clause (iii) of the immediately
preceding paragraph, such Liquidated Damages Amount shall be paid only to the
Holders that have delivered Notice and Questionnaires that caused the Company to
incur the obligations set forth in Section 2(d) the non-performance of which is
the basis of such Event; provided further, that any Liquidated Damages Amount
accrued with respect to any Debenture or portion thereof called for redemption
on a redemption date or converted into Underlying Common Stock on a conversion
date prior to the Damages Payment Date, shall, in any such event, be paid
instead to the Holder who submitted such Debenture or portion thereof for
redemption or conversion on the applicable redemption date or conversion date,
as the case may be, on such date (or promptly following the conversion date, in
the case of conversion). Notwithstanding the foregoing, no Liquidated Damages
Amounts shall accrue as to any Registrable Security from and after the earlier
of (x) the date such security is no longer a Registrable Security and (y)
expiration of the Effectiveness Period.  The rate of accrual of the Liquidated
Damages Amount with respect to any period shall not exceed the rate provided for
in this paragraph notwithstanding the occurrence of multiple 

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concurrent Events. Following the cure of all Events requiring the payment by the
Company of Liquidated Damages Amounts to the Holders of Registrable Securities
pursuant to this Section, the accrual of Liquidated Damages Amounts will cease
(without in any way limiting the effect of any subsequent Event requiring the
payment of Liquidated Damages Amount by the Company).

     The Trustee shall be entitled, on behalf of Holders of Debentures or
Underlying Common Stock, to seek any available remedy for the enforcement of
this Agreement, including for the payment of any Liquidated Damages Amount.
Notwithstanding the foregoing, the parties agree that the sole damages payable
for a violation of the terms of this Agreement with respect to which liquidated
damages are expressly provided shall be such liquidated damages. Nothing shall
preclude a Notice Holder or Holder of Registrable Securities from pursuing or
obtaining specific performance or other equitable relief with respect to this
Agreement.

     All of the Company's obligations set forth in this Section 2(e) that are
outstanding with respect to any Registrable Security at the time such security
ceases to be a Registrable Security shall survive until such time as all such
obligations with respect to such security have been satisfied in full
(notwithstanding termination of this Agreement pursuant to Section 8(k)).

     The parties hereto agree that the liquidated damages provided for in this
Section 2(e) constitute a reasonable estimate of the damages that may be
incurred by Holders of Registrable Securities by reason of the failure of the
Shelf Registration Statement to be filed or declared effective or available for
effecting resales of Registrable Securities in accordance with the provisions
hereof.

     Section 3.  Registration Procedures.  In connection with the registration
obligations of the Company under Section 2 hereof, the Company shall:

       (a)  Before filing any Registration Statement or Prospectus or any
amendments or supplements thereto with the SEC, furnish to the Purchasers copies
of all such documents proposed to be filed and use all reasonable efforts to
reflect in each such document when so filed with the SEC such comments as the
Purchasers reasonably shall propose within two (2) Business Days of the delivery
of such copies to the Purchasers.

       (b)  Prepare and file with the SEC such amendments and post-effective
amendments to each Registration Statement as may be necessary to keep such
Registration Statement continuously effective for the applicable period
specified in Section 2(a); cause the related Prospectus to be supplemented by
any required Prospectus supplement, and as so supplemented to be filed pursuant
to Rule 424 (or any similar provisions then in force) under the Securities Act;
and use all reasonable efforts to comply with the provisions of the Securities
Act applicable to it with respect to the disposition of all securities covered
by such Registration Statement during the Effectiveness Period in accordance
with the intended methods of disposition by the sellers thereof set forth in
such Registration Statement as so amended or such Prospectus as so supplemented.

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       (c)  As promptly as practicable give notice to the Notice Holders and the
Purchasers (i) when any Prospectus, Prospectus supplement, Registration
Statement or post-effective amendment to a Registration Statement has been filed
with the SEC and, with respect to a Registration Statement or any post-effective
amendment, when the same has been declared effective, (ii) of any request,
following the effectiveness of the Initial Shelf Registration Statement under
the Securities Act, by the SEC or any other federal or state governmental
authority for amendments or supplements to any Registration Statement or related
Prospectus or for additional information, (iii) of the issuance by the SEC or
any other federal or state governmental authority of any stop order suspending
the effectiveness of any Registration Statement or the initiation or threatening
of any proceedings for that purpose, (iv) of the receipt by the Company of any
notification with respect to the suspension of the qualification or exemption
from qualification of any of the Registrable Securities for sale in any
jurisdiction or the initiation or threatening of any proceeding for such
purpose, (v) of the occurrence of (but not the nature of or details concerning)
a Material Event (provided, however, that no notice by the Company shall be
                  --------  -------                                        
required pursuant to this clause (v) in the event that the Company either
promptly files a Prospectus supplement to update the Prospectus or a Form 8-K or
other appropriate Exchange Act report that is incorporated by reference into the
Registration Statement, which, in either case, contains the requisite
information with respect to such Material Event that results in such
Registration Statement no longer containing any untrue statement of material
fact or omitting to state a material fact necessary to make the statements
contained therein not misleading) and (vi) of the determination by the Company
that a post-effective amendment to a Registration Statement will be filed with
the SEC, which notice may, at the discretion of the Company (or as required
pursuant to Section 3(i)), state that it constitutes a Deferral Notice, in which
event the provisions of Section 3(i) shall apply.

       (d)  Use all reasonable efforts to obtain the withdrawal of any order
suspending the effectiveness of a Registration Statement or the lifting of any
suspension of the qualification (or exemption from qualification) of any of the
Registrable Securities for sale in any jurisdiction in which they have been
qualified for sale, in either case at the earliest possible moment.

       (e)  If reasonably requested by the Purchasers or any Notice Holder,
promptly as reasonably practicable incorporate in a Prospectus supplement or
post-effective amendment to a Registration Statement such information as the
Purchasers or such Notice Holder shall, on the basis of an opinion of
nationally-recognized counsel experienced in such matters, determine to be
required to be included therein by applicable law and make any required filings
of such Prospectus supplement or such post-effective amendment; provided, that
the Company shall not be required to take any actions under this Section 3(e)
that are not, in the reasonable opinion of counsel for the Company, in
compliance with applicable law.

       (f)  Promptly as reasonably practicable furnish to each Notice Holder and
the Purchasers, upon their request and without charge, at least one (1)
conformed copy of the Registration Statement and any amendment thereto,
including financial statements but excluding schedules, all documents
incorporated or deemed to be incorporated therein by reference and all 

                                       9
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exhibits (unless requested in writing to the Company by such Notice Holder or
the Purchasers, as the case may be).

       (g)  During the Effectiveness Period, deliver to each Notice Holder in
connection with any sale of Registrable Securities pursuant to a Registration
Statement, without charge, as many copies of the Prospectus or Prospectuses
relating to such Registrable Securities (including each preliminary prospectus)
and any amendment or supplement thereto as such Notice Holder may reasonably
request; and the Company hereby consents (except during such periods that a
Deferral Notice is outstanding and has not been revoked) to the use of such
Prospectus or each amendment or supplement thereto by each Notice Holder in
connection with any offering and sale of the Registrable Securities covered by
such Prospectus or any amendment or supplement thereto in the manner set forth
therein.

       (h)  Prior to any public offering of the Registrable Securities pursuant
to the Shelf Registration Statement, use its reasonable efforts to register or
qualify or cooperate with the Notice Holders in connection with the registration
or qualification (or exemption from such registration or qualification) of such
Registrable Securities for offer and sale under the securities or Blue Sky laws
of such jurisdictions within the United States as any Notice Holder reasonably
requests in writing (which request may be included in the Notice and
Questionnaire); prior to any public offering of the Registrable Securities
pursuant to the Shelf Registration Statement, use its reasonably efforts to keep
each such registration or qualification (or exemption therefrom) effective
during the Effectiveness Period in connection with such Notice Holder's offer
and sale of Registrable Securities pursuant to such registration or
qualification (or exemption therefrom) and do any and all other acts or things
necessary or advisable to enable the disposition in such jurisdictions of such
Registrable Securities in the manner set forth in the relevant Registration
Statement and the related Prospectus; provided, that the Company will not be
required to (i) qualify as a foreign corporation or as a dealer in securities in
any jurisdiction where it would not otherwise be required to qualify but for
this Agreement or (ii) take any action that would subject it to general service
of process in suits or to taxation in any such jurisdiction where it is not then
so subject.

       (i)  Upon (A) the issuance by the SEC of a stop order suspending the
effectiveness of the Shelf Registration Statement or the initiation of
proceedings with respect to the Shelf Registration Statement under Section 8(d)
or 8(e) of the Securities Act, (B) the occurrence of any event or the existence
of any fact (a "Material Event") as a result of which any Registration Statement
shall contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary to make the statements
therein not misleading, or any Prospectus shall contain any untrue statement of
a material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading, or (C) the occurrence or existence
of any pending corporate development that, in the discretion of the Company,
makes it appropriate to suspend the availability of the Shelf Registration
Statement and the related Prospectus, (i) in the case of clause (B) above,
subject to the next sentence, as promptly as practicable prepare and 

                                      10
<PAGE>
 
file, if necessary pursuant to applicable law, a post-effective amendment to
such Registration Statement or a supplement to the related Prospectus or any
document incorporated therein by reference or file any other required document
that would be incorporated by reference into such Registration Statement and
Prospectus so that such Registration Statement does not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading, and
such Prospectus does not contain any untrue statement of a material fact or omit
to state any material fact required to be stated therein or necessary to make
the statements therein, in the light of the circumstances under which they were
made, not misleading, as thereafter delivered to the purchasers of the
Registrable Securities being sold thereunder, and, in the case of a post-
effective amendment to a Registration Statement, subject to the next sentence,
use all reasonable efforts to cause it to be declared effective as promptly as
is reasonably practicable, and (ii) give notice to the Notice Holders that the
availability of the Shelf Registration Statement is suspended (a "Deferral
Notice") and, upon receipt of any Deferral Notice, each Notice Holder agrees not
to sell any Registrable Securities pursuant to the Registration Statement until
such Notice Holder's receipt of copies of the supplemented or amended Prospectus
provided for in clause (i) above, or until it is advised in writing by the
Company that the Prospectus may be used, and has received copies of any
additional or supplemental filings that are incorporated or deemed incorporated
by reference in such Prospectus. The Company will use all reasonable efforts to
ensure that the use of the Prospectus may be resumed (x) in the case of clause
(A) above, as promptly as is practicable, (y) in the case of clause (B) above,
as soon as, in the sole judgment of the Company, public disclosure of such
Material Event would not be prejudicial to or contrary to the interests of the
Company or, if necessary to avoid unreasonable burden or expense, as soon as
reasonably practicable thereafter and (z) in the case of clause (C) above, as
soon as, in the discretion of the Company, such suspension is no longer
appropriate. The period during which the availability of the Registration
Statement and any Prospectus is suspended (the "Deferral Period") shall, without
the Company incurring any obligation to pay liquidated damages pursuant to
Section 2(e), not exceed forty-five (45) days in any three (3) month period or
ninety (90) days in any twelve (12) month period.

       (j)  If reasonably requested in writing in connection with a disposition
of Registrable Securities pursuant to a Registration Statement, make reasonably
available for inspection during normal business hours by a representative for
the Notice Holders of such Registrable Securities and any broker-dealers,
attorneys and accountants retained by such Notice Holders, all relevant
financial and other records, pertinent corporate documents and properties of the
Company and its subsidiaries, and cause the appropriate executive officers,
directors and designated employees of the Company and its subsidiaries to make
reasonably available for inspection during normal business hours all relevant
information reasonably requested by such representative for the Notice Holders
or any such broker-dealers, attorneys or accountants in connection with such
disposition, in each case as is customary for similar "due diligence"
examinations; provided, however, that such persons shall first agree in writing
with the Company that any information that is reasonably and in good faith
designated by the Company in writing as confidential at the time of delivery of
such information shall be kept confidential by such persons and shall be used

                                      11
<PAGE>
 
solely for the purposes of exercising rights under this Agreement, unless (i)
disclosure of such information is required by court or administrative order or
is necessary to respond to inquiries of regulatory authorities, (ii) disclosure
of such information is required by law (including any disclosure requirements
pursuant to federal securities laws in connection with the filing of any
Registration Statement or the use of any Prospectus referred to in this
Agreement), (iii) such information becomes generally available to the public
other than as a result of a disclosure or failure to safeguard by any such
person or (iv) such information becomes available to any such person from a
source other than the Company and such source is not bound by a confidentiality
agreement; and provided further, that the foregoing inspection and information
gathering shall, to the greatest extent possible, be coordinated on behalf of
all the Notice Holders and the other parties entitled thereto by the counsel
referred to in Section 5.

       (k)  Use all reasonable efforts to comply with all applicable rules and
regulations of the SEC and make generally available to its securityholders
earning statements (which need not be audited) satisfying the provisions of
Section 11(a) of the Securities Act and Rule 158 thereunder (or any similar rule
promulgated under the Securities Act) no later than 45 days after the end of any
12-month period (or 90 days after the end of any 12-month period if such period
is a fiscal year) commencing on the first day of the first fiscal quarter of the
Company commencing after the effective date of a Registration Statement, which
statements shall cover said 12-month periods.

       (l)  Cooperate with each Notice Holder to facilitate the timely
preparation and delivery of certificates representing Registrable Securities
sold pursuant to a Registration Statement, and cause such Registrable Securities
to be in such denominations as are permitted by the Indenture and registered in
such names as such Notice Holder may request in writing at least two Business
Days prior to any sale of such Registrable Securities.

       (m)  Provide a CUSIP number for all Registrable Securities covered by
each Registration Statement not later than the effective date of such
Registration Statement and provide the Trustee and the transfer agent for the
Common Stock with printed certificates for the Registrable Securities that are
in a form eligible for deposit with The Depository Trust Company.

       (n)  Make a reasonable effort to provide such information as is required
for any filings required to be made with the National Association of Securities
Dealers, Inc.

       (o)  Upon (i) the filing of the Initial Shelf Registration Statement and
(ii) the effectiveness of the Initial Shelf Registration Statement, announce the
same, in each case by release to Reuters Economic Services and Bloomberg
Business News.


     Section 4.  Holder's Obligations.  Each Holder agrees, by acquisition of
the Registrable Securities, that no Holder of Registrable Securities shall be
entitled to sell any of such Registrable Securities pursuant to a Registration
Statement or to receive a Prospectus relating thereto, unless such Holder has
furnished the Company with a Notice and Questionnaire as 

                                      12
<PAGE>
 
required pursuant to Section 2(d) hereof (including the information required to
be included in such Notice and Questionnaire) and the information set forth in
the next sentence. Each Notice Holder agrees promptly to furnish to the Company
all information required to be disclosed in order to make the information
previously furnished to the Company by such Notice Holder not misleading and any
other information regarding such Notice Holder and the distribution of such
Registrable Securities as may be required to be disclosed in the Registration
Statement or that the Company may from time to time reasonably request. Any sale
of any Registrable Securities by any Holder shall constitute a representation
and warranty by such Holder that the information relating to such Holder and its
plan of distribution is as set forth in the Prospectus delivered by such Holder
in connection with such disposition, that such Prospectus does not as of the
time of such sale contain any untrue statement of a material fact relating to or
provided by such Holder or its plan of distribution and that such Prospectus
does not as of the time of such sale omit to state any material fact relating to
or provided by such Holder or its plan of distribution necessary to make the
statements in such Prospectus, in the light of the circumstances under which
they were made, not misleading.

     Section 5.  Registration Expenses.   The Company shall bear all fees and
expenses incurred in connection with the performance by the Company of its
obligations under Sections 2 and 3 of this Agreement whether or not any of the
Registration Statements are declared effective. Such fees and expenses shall
include, without limitation, (i) all registration and filing fees (including,
without limitation, fees and expenses (x) with respect to filings required to be
made with the National Association of Securities Dealers, Inc. and (y) of
compliance with federal and state securities or Blue Sky laws (including,
without limitation, reasonable fees and disbursements of the counsel specified
in the next sentence in connection with Blue Sky qualifications of the
Registrable Securities under the laws of such jurisdictions as the Notice
Holders of a majority of the Registrable Securities being sold pursuant to a
Registration Statement may designate), (ii) printing expenses (including,
without limitation, expenses of printing certificates for Registrable Securities
in a form eligible for deposit with The Depository Trust Company), (iii)
duplication expenses relating to copies of any Registration Statement or
Prospectus delivered to any Holders hereunder, (iv) fees and disbursements of
counsel for the Company in connection with the Shelf Registration Statement, and
(v) reasonable fees and disbursements of the Trustee and its counsel and of the
registrar and transfer agent for the Common Stock. In addition, the Company
shall bear or reimburse the Notice Holders for the reasonable fees and
disbursements (not to exceed $15,000) of one firm of legal counsel for the
Holders, which shall initially be Wilson Sonsini Goodrich & Rosati, P.C., but
which may, with the written consent of the Purchasers (which shall not be
unreasonably withheld), be another nationally recognized law firm experienced in
securities law matters designated by the Company. In addition, the Company shall
pay the internal expenses of the Company (including, without limitation, all
salaries and expenses of officers and employees performing legal or accounting
duties), the expense of any annual audit, the fees and expenses incurred in
connection with the listing of the Registrable Securities on any securities
exchange on which similar securities of the Company are then listed and the fees
and expenses of any person, including special experts, retained by the Company.
Notwithstanding the provisions of this Section 5, each seller of 

                                      13
<PAGE>
 
Registrable Securities shall pay all registration expenses to the extent
required by applicable law.

     Section 6.  Indemnification.

     (a)  Indemnification by the Company.  The Company shall indemnify and
hold harmless each Notice Holder and each person, if any, who controls any
Notice Holder (within the meaning of either Section 15 of the Securities Act or
Section 20 of the Exchange Act) from and against all losses, liabilities,
claims, damages and expenses (including, without limitation, any legal or other
expenses reasonably incurred in connection with defending or investigating any
such action or claim) (collectively, "Losses"), arising out of or based upon any
untrue statement or alleged untrue statement of a material fact contained in any
Registration Statement or Prospectus or in any amendment or supplement thereto
or in any preliminary prospectus, or arising out of or based upon any omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, provided,
however, that the Company shall not be liable in any such case to the extent
that any such Losses arise out of or are based upon an untrue statement or
alleged untrue statement contained in or omission or alleged omission from any
of such documents in reliance upon and conformity with any of the information
relating to such Holder furnished to the Company in writing by such Holder
expressly for use therein; provided further, that the indemnification contained
in this paragraph shall not inure to the benefit of any Holder of Registrable
Securities (or to the benefit of any person controlling such Holder) on account
of any such Losses arising out of or based upon an untrue statement or alleged
untrue statement or omission or alleged omission made in any preliminary
prospectus if either (A) (i) such Holder failed to send or deliver a copy of the
Prospectus with or prior to the delivery of written confirmation of the sale by
such Holder to the person asserting the claim from which such Losses arise and
(ii) the Prospectus would have corrected such untrue statement or alleged untrue
statement or such omission or alleged omission, or (B) (x) such untrue statement
or alleged untrue statement, omission or alleged omission is corrected in an
amendment or supplement to the Prospectus and (y) having previously been
furnished by or on behalf of the Company with copies of the Prospectus as so
amended or supplemented, such Holder thereafter fails to deliver such Prospectus
as so amended or supplemented, with or prior to the delivery of written
confirmation of the sale of a Registrable Security to the person asserting the
claim from which such Losses arise.

       (b)  Indemnification by Holders of Registrable Securities.  Each Holder
agrees severally and not jointly to indemnify and hold harmless the Company and
its respective directors and officers, and each person, if any, who controls the
Company (within the meaning of either Section 15 of the Securities Act or
Section 20 of the Exchange Act), from and against all Losses arising out of or
based upon any untrue statement or alleged untrue statement of a material fact
contained in any Registration Statement or Prospectus or in any amendment or
supplement thereto or in any preliminary prospectus, or arising out of or based
upon any omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein not misleading,
to the extent, but only to the extent, that such untrue statement or alleged
untrue statement or omission or alleged omission was made in reliance upon and
in 

                                      14
<PAGE>
 
conformity with information furnished to the Company by such Holder expressly
for use in such Registration Statement or Prospectus or amendment or supplement
thereto. In no event shall the liability of any selling Holder of Registrable
Securities hereunder be greater in amount than the dollar amount of the proceeds
received by such Holder upon the sale of the Registrable Securities pursuant to
the Registration Statement giving rise to such indemnification obligation.

       (c)  Conduct of Indemnification Proceedings.  In case any proceeding
(including any governmental investigation) shall be instituted involving any
person in respect of which indemnity may be sought pursuant to either of the two
preceding paragraphs, such person (the "indemnified party") shall promptly
notify the person against whom such indemnity may be sought (the "indemnifying
party") in writing and the indemnifying party, upon request of the indemnified
party, shall retain counsel reasonably satisfactory to the indemnified party to
represent the indemnified party and any others the indemnifying party may
designate in such proceeding and shall pay the reasonable fees and disbursements
of such counsel related to such proceeding.  In any such proceeding, any
indemnified party shall have the right to retain its own counsel, but the fees
and expenses of such counsel shall be at the expense of such indemnified party
unless (i) the indemnifying party and the indemnified party shall have mutually
agreed to the retention of such counsel or (ii) the named parties to any such
proceeding (including any impleaded parties) include both the indemnifying party
and the indemnified party and representation of both parties by the same counsel
would be inappropriate due to actual or potential differing interests between
them.  It is understood that the indemnifying party shall not, in respect of the
legal expenses of any indemnified party in connection with any proceeding or
related proceedings in the same jurisdiction, be liable for the fees and
expenses of more than one separate firm (in addition to any local counsel) for
all indemnified parties, and that all such fees and expenses shall be reimbursed
as they are incurred.  Such separate firm shall be designated in writing by, in
the case of parties indemnified pursuant to Section 6(a), the Holders of a
majority (with Holders of Debentures deemed to be the Holders, for purposes of
determining such majority, of the number of shares of Underlying Common Stock
into which such Debentures are or would be convertible or exchangeable as of the
date on which such designation is made) of the Registrable Securities covered by
the Registration Statement held by Holders that are indemnified parties pursuant
to Section 6(a) and, in the case of parties indemnified pursuant to Section
6(b), the Company.  The indemnifying party shall not be liable for any
settlement of any proceeding effected without its written consent, but if
settled with such consent or if there be a final judgment for the plaintiff, the
indemnifying party agrees to indemnify the indemnified party from and against
any loss or liability by reason of such settlement or judgment.  No indemnifying
party shall, without the prior written consent of the indemnified party, effect
any settlement of any pending or threatened proceeding in respect of which any
indemnified party is or could have been a party and indemnity could have been
sought hereunder by such indemnified party, unless such settlement includes an
unconditional release of such indemnified party from all liability on claims
that are the subject matter of such proceeding (and in the event of a settlement
that involves an unconditional release of such indemnified party, the
indemnifying party will send prompt written notice of such settlement to the
indemnified party).

                                      15
<PAGE>
 
       (d)  Contribution.  To the extent that the indemnification provided for
in this Section 6 is unavailable to an indemnified party under Section 6(a) or
6(b) hereof in respect of any Losses or is insufficient to hold such indemnified
party harmless, then each applicable indemnifying party, in lieu of indemnifying
such indemnified party, shall contribute to the amount paid or payable by such
indemnified party as a result of such Losses (i) in such proportion as is
appropriate to reflect the relative benefits received by the indemnifying party
or parties on the one hand and the indemnified party or parties on the other
hand 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 indemnifying party or parties on the one hand and of the indemnified party
or parties on the other hand in connection with the statements or omissions that
resulted in such Losses, as well as any other relevant equitable considerations.
Benefits received by the Company shall be deemed to be equal to the total net
proceeds from the initial placement pursuant to the Purchase Agreement (before
deducting expenses) of the Registrable Securities to which such Losses relate.
Benefits received by any Holder shall be deemed to be equal to the value of
receiving Registrable Securities that are registered under the Securities Act.
The relative fault of the Holders on the one hand and the Company on the other
hand shall be determined by reference to, among other things, whether the untrue
or alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the Holders
or by the Company, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The Holders' respective obligations to contribute pursuant to this paragraph are
several in proportion to the respective number of Registrable Securities they
have sold pursuant to a Registration Statement, and not joint.

     The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 6(d) were determined by pro rata
                                                              --- ----
allocation or by any other method or allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
The amount paid or payable by an indemnified party as a result of the Losses
referred to in the immediately preceding paragraph shall be deemed to include,
subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such indemnified party in connection with investigating
or defending any such action or claim.  Notwithstanding this Section 6(d), an
indemnifying party that is a selling Holder of Registrable Securities shall not
be required to contribute any amount in excess of the amount by which the total
price at which the Registrable Securities sold by such indemnifying party and
distributed to the public were offered to the public exceeds the amount of any
damages that such indemnifying party has otherwise been required to pay by
reason of such 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.

       (e)  The indemnity, contribution and expense reimbursement obligations of
the parties hereunder shall be in addition to any liability any indemnified
party may otherwise have hereunder, under the Purchase Agreement or otherwise.

                                      16
<PAGE>
 
       (f)  The indemnity and contribution provisions contained in this Section
6 shall remain operative and in full force and effect regardless of (i) any
termination of this Agreement, (ii) any investigation made by or on behalf of
any Holder or any person controlling any Holder, or the Company, or the
Company's officers or directors or any person controlling the Company and (iii)
the sale of any Registrable Securities by any Holder.


     Section 7.  Information Requirements.  (a) The Company covenants that, if
at any time before the end of the Effectiveness Period the Company is not
subject to the reporting requirements of the Exchange Act, it will cooperate
with any Holder of Registrable Securities and take such further reasonable
action as any Holder of Registrable Securities may reasonably request in writing
(including, without limitation, making such reasonable representations as any
such Holder may reasonably request), all to the extent required from time to
time to enable such Holder to sell Registrable Securities without registration
under the Securities Act within the limitation of the exemptions provided by
Rule 144 and Rule 144A under the Securities Act and customarily taken in
connection with sales pursuant to such exemptions. Upon the written request of
any Holder of Registrable Securities, the Company shall deliver to such Holder a
written statement as to whether it has complied with such filing requirements,
unless such a statement has been included in the Company's most recent report
required to be filed and filed pursuant to Section 13 or Section 15(d) of
Exchange Act. Notwithstanding the foregoing, nothing in this Section 7 shall be
deemed to require the Company to register any of its securities (other than the
Common Stock) under any section of the Exchange Act.

     Section 8.  Miscellaneous.

     (a)  No Conflicting Agreements.  The Company is not, as of the date
hereof, a party to, nor shall it, on or after the date of this Agreement, enter
into, any agreement with respect to its securities that conflicts with the
rights granted to the Holders of Registrable Securities in this Agreement.  The
Company represents and warrants that the rights granted to the Holders of
Registrable Securities hereunder do not in any way conflict with the rights
granted to the holders of the Company's securities under any other agreements.

     (b)  Amendments and Waivers.  The provisions of this Agreement, including
the provisions of this sentence, may not be amended, modified or supplemented,
and waivers or consents to departures from the provisions hereof may not be
given, unless the Company has obtained the written consent of Holders of a
majority of the then outstanding Underlying Common Stock constituting
Registrable Securities (with Holders of Debentures deemed to be the Holders, for
purposes of this Section, of the number of outstanding shares of Underlying
Common Stock into which such Debentures are or would be convertible or
exchangeable as of the date on which such consent is requested).
Notwithstanding the foregoing, a waiver or consent to depart from the provisions
hereof with respect to a matter that relates exclusively to the rights of
Holders of Registrable Securities whose securities are being sold pursuant to a
Registration Statement and that does not directly or indirectly affect the
rights of other Holders 

                                      17
<PAGE>
 
of Registrable Securities may be given by Holders of at least a majority of the
Registrable Securities being sold by such Holders pursuant to such Registration
Statement; provided, that the provisions of this sentence may not be amended,
modified, or supplemented except in accordance with the provisions of the
immediately preceding sentence. Each Holder of Registrable Securities
outstanding at the time of any such amendment, modification, supplement, waiver
or consent or thereafter shall be bound by any such amendment, modification,
supplement, waiver or consent effected pursuant to this Section 8(b), whether or
not any notice, writing or marking indicating such amendment, modification,
supplement, waiver or consent appears on the Registrable Securities or is
delivered to such Holder.

     (c)  Notices.  All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, by telecopier, by
courier guaranteeing overnight delivery or by first-class mail, return receipt
requested, and shall be deemed given (i) when made, if made by hand delivery,
(ii) upon confirmation, if made by telecopier, (iii) one (1) Business Day after
being deposited with such courier, if made by overnight courier or (iv) on the
date indicated on the notice of receipt, if made by first-class mail, to the
parties as follows:


          (w) if to a Holder of Registrable Securities, at the most current
          address given by such Holder to the Company in a Notice and
          Questionnaire or any amendment thereto;


          (x)  if to the Company, to:


                  At Home Corporation
                  425 Broadway Street
                  Redwood City, CA  94063
                  Attention: General Counsel
                  Telecopy No.: (650) 569-5100

                  and


          (y)  if to the Purchasers, to:

                  Merrill Lynch & Co., Merrill Lynch, Pierce, Fenner & Smith
                  Incorporated
                  World Financial Center
                  North Tower
                  250 Vesey Street
                  New York, New York  10281
                  Attention:  Syndicate Department
                  Telecopy No.: (212) 449-1000


or to such other address as such person may have furnished to the other persons
identified in this Section 8(c) in writing in accordance herewith.

                                      18
<PAGE>
 
       (d)  Approval of Holders.  Whenever the consent or approval of Holders of
a specified percentage of Registrable Securities is required hereunder,
Registrable Securities held by the Company or its affiliates (as such term is
defined in Rule 405 under the Securities Act) (other than the Purchasers or
subsequent Holders of Registrable Securities if such subsequent Holders are
deemed to be such affiliates solely by reason of their holdings of such
Registrable Securities) shall not be counted in determining whether such consent
or approval was given by the Holders of such required percentage.

       (e)  Successors and Assigns.  Any person who purchases any Registrable
Securities from the Purchasers shall be deemed, for purposes of this Agreement,
to be an assignee of the Purchasers.  This Agreement shall inure to the benefit
of and be binding upon the successors and assigns of each of the parties and
shall inure to the benefit of and be binding upon each Holder of any Registrable
Securities.

       (f)  Counterparts.  This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be original and all of which taken together
shall constitute one and the same agreement.

       (g)  Headings.  The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

       (h)  Governing Law.  THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO CONFLICTS
OF LAWS PRINCIPLES THEREOF.

       (i)  Severability.  If any term, provision, covenant or restriction of
this Agreement is held to be invalid, illegal, void or unenforceable, the
remainder of the terms, provisions, covenants and restrictions set forth herein
shall remain in full force and effect and shall in no way be affected, impaired
or invalidated thereby, and the parties hereto shall use their best efforts to
find and employ an alternative means to achieve the same or substantially the
same result as that contemplated by such term, provision, covenant or
restriction, it being intended that all of the rights and privileges of the
parties shall be enforceable to the fullest extent permitted by law.

       (j)  Entire Agreement.  This Agreement is intended by the parties as a
final expression of their agreement and is intended to be a complete and
exclusive statement of the agreement and understanding of the parties hereto in
respect of the subject matter contained herein and the registration rights
granted by the Company with respect to the Registrable Securities.  Except as
provided in the Purchase Agreement, there are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein,
with respect to the registration rights granted by the Company with respect to
the Registrable Securities.  This Agreement supersedes all prior agreements and
undertakings among the parties with respect to such registration rights.  No
party hereto shall have any rights, duties or obligations other than those

                                      19
<PAGE>
 
specifically set forth in this Agreement.  Without limiting the generality of
the foregoing, the Company shall have no obligation to participate in "road
show" or, except as specifically provided in this Agreement, "due diligence"
activities in connection with any underwritten public offering of Registrable
Securities, and the Company shall have no obligation to enter into underwriting
or indemnification agreements with respect to, or deliver opinions, comfort
letters or closing certificates in connection with, any such underwritten public
offering.

       (k)  Termination.  This Agreement and the obligations of the parties
hereunder shall terminate upon the end of the Effectiveness Period, except for
any liabilities or obligations under Sections 4, 5 or 6 hereof and the
obligations to make payments of and provide for liquidated damages under Section
2(e) hereof to the extent such damages accrue prior to the end of the
Effectiveness Period, each of which shall remain in effect in accordance with
its terms.



               [Remainder of this page intentionally left blank]

                                      20
<PAGE>
 
IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement
as of the date first written above.



                            AT HOME CORPORATION



                            By: /s/ Kenneth A. Goldman
                                ----------------------------------
                                Name:   Kenneth A. Goldman
                                Title:  Senior Vice President and
                                        Chief Financial Officer

Accepted as of the date first
above written:

MERRILL LYNCH & CO., MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED
(for the benefit of the Purchasers and for the benefit of the Holders)


By:  MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED



By:  /s/ Matt Pendro
     ----------------------------
    Name:  Matt Pendo
    Title: Managing Director

                                      21