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                                                                    EXHIBIT 99.1

                              SUMMARY OF THE RIGHTS


        On September 10, 1998 (the "RIGHTS DIVIDEND DECLARATION DATE"), the
Board of Directors of Western Digital Corporation (the "CORPORATION") declared a
dividend of one right (a "RIGHT") to purchase fractions of shares of its Series
A Junior Participating Preferred Stock, having the rights, preferences,
privileges and restrictions described in Paragraph K below (the "PREFERRED
STOCK"), and, under certain circumstances, other securities, for each
outstanding share of the Corporation's common stock, par value $.01 per share
(the "COMMON STOCK"), to be distributed to stockholders of record at the close
of business on November 30, 1998 (the "RECORD DATE"). The description and terms
of the Rights are set forth in a Rights Agreement (the "RIGHTS AGREEMENT") dated
as of October 15, 1998 between the Corporation and American Stock Transfer &
Trust Company, as Rights Agent.

        The following is a brief description of the Rights. It is intended to
provide a general description only and is qualified in its entirety by reference
to the Rights Agreement, which has been filed as an exhibit to the Corporation's
Registration Statement on Form 8-A filed with the Securities and Exchange
Commission concurrently herewith.

A.      ISSUANCE OF THE RIGHTS

        Each share of Common Stock outstanding at the close of business on the
Record Date will receive one Right. In addition, prior to the earliest of the
Distribution Date, a Section 13 Event or the Expiration Date (as each is
hereinafter defined), one additional Right (as such number may be adjusted
pursuant to the provisions of the Rights Agreement) shall be issued with each
share of Common Stock issued after the Record Date. Following the Distribution
Date and prior to the expiration or redemption of the Rights, the Corporation
will issue one Right (as such number may be adjusted pursuant to the provisions
of the Rights Agreement) for each share of Common Stock issued pursuant to the
exercise of stock options or under employee plans or upon the exercise,
conversion or exchange of securities issued by the Corporation prior to the
Distribution Date. A "SECTION 13 EVENT" shall mean any event in which (i) the
Corporation merges or consolidates with another and the Corporation is not the
surviving corporation; (ii) the Corporation merges or consolidates with another,
the Corporation is the surviving corporation, and all or part of the
Corporation's common stock is exchanged for other securities, cash or property;
or (iii) the Corporation sells or transfers more than 50% of its assets or
earning power. The "EXPIRATION DATE" shall mean the earliest of (i) October 14,
2008; (ii) the date of redemption of the Rights; (iii) the date the Board orders
an exchange of Rights; or (iv) the date of consummation of a tender offer
approved as fair to and in the best interests of the Corporation and its
stockholders and adequately priced with each stockholder receiving the same
consideration per share in the same manner.
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B.      COMMON STOCK CERTIFICATES REPRESENT THE RIGHTS PRIOR TO THE DISTRIBUTION
        DATE

        Prior to the Distribution Date (as hereinafter defined), no separate
Rights certificates will be issued. Instead, the Rights will be evidenced by the
certificates for the Common Stock to which they are attached and will be
transferred with and only with such Common Stock certificates. The surrender for
transfer of any certificates for Common Stock outstanding will also constitute
the transfer of the Rights associated with the Common Stock represented by such
certificate. New Common Stock certificates issued after the Record Date will
contain a legend incorporating the Rights Agreement by reference.

C.      DISTRIBUTION DATE; ISSUANCE OF RIGHTS CERTIFICATES

        The Rights will separate from the Common Stock and become exercisable
and a Distribution Date will occur (the "DISTRIBUTION DATE") upon the earlier of
the close of business on the tenth day after (i) public announcement that a
person or group of affiliated or associated persons has acquired beneficial
ownership of 15% or more of the outstanding shares of Common Stock (an
"ACQUIRING PERSON") or such earlier date as a majority of the directors shall
become aware of the existence of an Acquiring Person (the "STOCK ACQUISITION
DATE"), or (ii) the commencement of a tender or exchange offer by any person or
group, if upon consummation thereof, such person or group of affiliated or
associated persons would be the beneficial owner of 15% or more of the shares of
Common Stock then outstanding. As soon as practicable after the Distribution
Date, Rights certificates will be mailed to holders of record of the Common
Stock as of the close of business on the Distribution Date and, thereafter, the
separate Rights certificates alone will represent the Rights.

D.      EXERCISE OF THE RIGHTS

        1. RIGHTS INITIALLY NOT EXERCISABLE. Prior to the Distribution Date, the
Rights are not exercisable.

        2. EXERCISE OF THE RIGHTS TO PURCHASE PREFERRED STOCK OF THE
CORPORATION. At any time after the Distribution Date but prior to the earlier of
the expiration, exchange or redemption of the Rights, each Right may be
exercised at the stated purchase price of $150 (subject to adjustment, the
"EXERCISE PRICE") for one one-thousandth of a share of the Preferred Stock;
provided, however, that upon the occurrence of any of the events described below
the Rights may no longer be exercised for the Preferred Stock and may only be
exercised for certain other securities described below.

        3. EXERCISE OF THE RIGHTS TO PURCHASE COMMON STOCK OF THE CORPORATION.
In the event that at any time following the Rights Dividend Declaration Date, a
person, alone or with affiliates, becomes the beneficial owner of 15% or more of
the then outstanding shares of the Corporation's Common Stock (except pursuant
to an offer for all outstanding shares of Common Stock which is determined by
both (i) the Board of Directors acting by Special Vote, and (ii) a majority of
the Directors who are not associated with an Acquiring Person ("CONTINUING
DIRECTORS") and who are also not employees of the Corporation, to be fair to and
otherwise in the 

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best interests of the Corporation and its stockholders (a "PERMITTED OFFER")),
then each holder of a Right will thereafter have the right to exercise the Right
for Common Stock (or, in certain circumstances, cash, property or other
securities of the Corporation) having a value equal to two times the Exercise
Price of the Right. If the Corporation does not have sufficient Common Shares
available for all Rights to be exercised, the Corporation may substitute for all
or any portion of the Common Stock that would be issuable upon exercise of the
Rights, cash, assets, or other securities having the same aggregate value as
such Common Stock. The Rights are exercisable as described in this paragraph
only after the Corporation's right of redemption (as described below) has
expired. Notwithstanding any of the foregoing, following the occurrence of the
event set forth in this paragraph (a "SECTION 11(a)(ii) EVENT"), all Rights that
are, or under certain circumstances specified in the Rights Agreement were,
beneficially owned by an Acquiring Person will be null and void. A "SPECIAL
VOTE" of the Board of Directors is approval by both a majority of the Continuing
Directors and a majority of the entire Board, including the Continuing
Directors.

        4. EXERCISE OF THE RIGHTS TO PURCHASE COMMON STOCK OF AN ACQUIRING
CORPORATION. In the event that, at any time following the Stock Acquisition
Date, (i) the Corporation is merged or consolidated with another company in a
business combination transaction in which the Corporation is not the surviving
corporation or in which the Corporation is the surviving corporation and all or
part of the Common Stock of the Corporation is exchanged for stock of any other
person, cash or any other property (other than a merger which follows a
Permitted Offer), or (ii) more than 50% of the assets or earning power of the
Corporation and its subsidiaries (taken as a whole) is sold or transferred, then
each holder of a Right (except Rights which previously have been voided as set
forth above) shall thereafter have the right to exercise the Right for common
stock of the acquiring company having a value equal to two times the Exercise
Price of the Right. (An event described in this paragraph is a "SECTION 13
EVENT.")

        5. ADJUSTMENT OF NUMBER OF RIGHTS, PURCHASE PRICE AND NUMBER OF UNITS OF
PREFERRED STOCK. The Exercise Price payable and/or the number of shares of
Preferred Stock or other securities or property issuable upon exercise of the
Rights are subject to proportionate adjustment from time to time to prevent
dilution (i) in the event of a stock dividend on, or a subdivision, combination
or reclassification of, the Preferred Stock, (ii) in the event holders of the
Preferred Stock are granted certain rights or warrants to subscribe for
Preferred Stock or convertible securities at less than the current market price
of the Preferred Stock, or (iii) upon the distribution to holders of the
Preferred Stock of evidences of indebtedness or assets (excluding cash
dividends) or of subscription rights or warrants (other than those referred to
above). If at any time after the Rights Dividend Declaration Date and prior to
the Distribution Date the Corporation declares a stock dividend on, subdivides
or combines the outstanding shares of Common Stock, the number of Rights
associated with each share of Common Stock shall be proportionately adjusted.

E.      FRACTIONAL RIGHTS AND FRACTIONAL SHARES

        The Corporation is generally not required to issue fractional Rights,
fractions of shares of Preferred Stock (other than fractions which are integral
multiples of one one-thousandth of a 


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share), or fractions of shares of Common Stock and, in lieu thereof, an
adjustment in cash will be made based on the market price of the Rights,
Preferred Stock, or Common Stock, respectively.

F.      REDEMPTION OF THE RIGHTS

        In general, the Corporation may redeem all (but not less than all) of
the Rights at a price of $.001 per Right (subject to adjustment to reflect stock
splits, stock dividends, or similar transactions), at any time until the earlier
of the tenth day following the Stock Acquisition Date or the close of business
on October 14, 2008 (provided that any redemption after any person becomes an
Acquiring Person may be effected only by the Board of Directors acting by
Special Vote). This redemption period may be extended by the Board of Directors
by amending the Rights Agreement as described in Paragraph H below prior to the
time when the Rights become nonredeemable. The redemption price may be paid in
cash, shares of Common Stock, or any other consideration the Board of Directors
deems appropriate. Immediately upon the action of the Board of Directors
ordering redemption of the Rights, the Rights will terminate and the only right
of the holders of Rights will be to receive the $.001 redemption price.

G.      EXCHANGE OF THE RIGHTS

        At any time after a Section 11(a)(ii) Event or a Section 13 Event and
before any person or group acquires 50% or more of the outstanding Common Stock,
the Board of Directors of the Corporation, acting by Special Vote, may cause the
Corporation to exchange some or all of the outstanding and exercisable Rights
for Common Stock at a one-to-one exchange ratio (appropriately adjusted to
reflect stock splits, dividends or similar transactions). Rights may not be
exercised after the Board orders their exchange. If there is not sufficient
authorized unissued Common Stock to fund an exchange, the Board, acting by
Special Vote, may fund the exchange through other consideration, including
issuance of debt and/or equity. In addition, at any time before any person or
group becomes in Acquiring Person, the Board, acting by Special Vote, may
exchange some or all of the Rights for rights of substantially equivalent value.

H.      AMENDMENTS

        Other than those provisions relating to the redemption price of the
Rights, any of the provisions of the Rights Agreement may be supplemented or
amended by the Board of Directors of the Corporation prior to the Distribution
Date, without approval of the Rights holders, whether or not a supplement or
amendment is adverse to the Rights holders. From and after the Distribution
Date, any provisions of the Rights Agreement (other than those provisions
relating to the redemption price of the Rights) may be amended by the Board of
Directors acting by Special Vote in order to (i) cure any ambiguous, defective
or inconsistent provision, (ii) shorten or lengthen any time period hereunder,
or (iii) otherwise change a provision which the Board of Directors acting by
Special Vote may deem necessary or desirable and which does not materially and
adversely affect the interests of holders of Rights (other than any Acquiring
Person); provided, the Rights Agreement may not be amended to (A) make the
Rights again redeemable after the Rights have ceased to be redeemable, or (B)
change any other time period unless such change is for the purpose of
protecting, enhancing or clarifying the rights of, and/or the benefits to the
holders of the Rights (other than any Acquiring Person).


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I.      EXPIRATION

        The Rights will expire upon the earliest to occur of the close of
business on October 14, 2008, the exchange or redemption of the Rights by the
Corporation, or the consummation of a Permitted Offer transaction followed by a
merger or consolidation of the Corporation with another company in which all
stockholders of the Corporation receive the same consideration and terms as in
the Permitted Offer.

J.      NO STOCKHOLDER RIGHTS PRIOR TO EXERCISE

        Until a Right is exercised, the holder thereof, as such, will have no
rights as a stockholder of the Corporation, including, without limitation, the
right to vote or to receive dividends.

K.      TERMS OF THE PREFERRED STOCK

        The Corporation has initially reserved 500,000 shares of Preferred Stock
for issuance upon exercise of the Rights, such number to be subject to
adjustment from time to time in accordance with the Rights Agreement. The
Preferred Stock will be nonredeemable. The dividend, liquidation and voting
rights, and the rights upon consolidation or merger of the Preferred Stock are
designed so that the value of the one one-thousandth interest in a share of
Preferred Stock purchasable with each Right will approximate the value of one
share of Common Stock. Each whole share of Preferred Stock will be entitled to
receive a quarterly preferential dividend equal to the greater of $.25 or 1,000
times any dividend declared on the Common Stock. In the event of liquidation,
the holders of the Preferred Stock will be entitled to receive a preferential
liquidation payment of $1,000 per share plus the amount of accrued unpaid
dividends thereon, the holders of the Common Stock will then be entitled to
receive a liquidation payment equal to $1.00 per share (subject to proportionate
adjustment to reflect stock splits, dividends or combinations), and the holders
of the Preferred Stock and Common Stock will then share ratably in all assets
remaining available for distribution to stockholders. Each share of Preferred
Stock will have 1,000 votes (subject to proportionate adjustment to reflect
stock splits, dividends and combinations), and will generally vote together with
the Common Stock. Finally, in the event of any merger, consolidation or other
transaction in which shares of Common Stock are exchanged for or changed into
other stock or securities, cash and/or other property, each share of Preferred
Stock will be entitled to receive 1,000 times the amount received per share of
Common Stock (subject to proportionate adjustment to reflect stock splits,
dividends and combinations).

L.      ANTI-TAKEOVER EFFECTS

        The Rights are designed to protect and maximize the value of
stockholders' interests in the Corporation in the event of an unsolicited
takeover attempt in a manner or on terms not approved by the Board of Directors.
Takeover attempts frequently include coercive tactics to deprive the Board of
Directors and stockholders of any real opportunity to determine the destiny of
the Corporation. The Rights have been declared by the Board in order to deter
such tactics, including a gradual accumulation in the open market of a 15% or
greater position, followed by a merger or a partial or two-tier tender offer
that does not treat all stockholders equally. These 

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tactics can unfairly pressure stockholders, squeeze them out of their investment
without giving them any real choice and deprive them of the full value of their
shares.

        The rights may be redeemed by the Corporation as described in Paragraph
F, and accordingly, the Rights should not interfere with any merger or business
combination approved by the Board of Directors.

        Issuance of the Rights does not weaken the Corporation or interfere with
its business plans. The issuance of the Rights themselves has no dilutive
effect, will not affect reported earnings per share, should not be taxable to
the Corporation or to its stockholders, and will not change the way in which the
Corporation's shares are presently traded. The Corporation's Board of Directors
believes that the Rights represent a sound and reasonable means of addressing
the complex issues of corporate policy created by the current takeover
environment.

        However, the Rights may have the effect of rendering more difficult or
discouraging an acquisition of the Corporation deemed undesirable by the Board
of Directors. The Rights may cause substantial dilution to a person or group
that attempts to acquire the Corporation on terms or in a manner not approved by
the Corporation's Board of Directors, except pursuant to an offer conditioned
upon the negation, purchase or redemption of the Rights.


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