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                                                                    EXHIBIT 10.6

                         STORAGE TECHNOLOGY CORPORATION
                              AMENDED AND RESTATED
                        1987 EMPLOYEE STOCK PURCHASE PLAN

                        AMENDED AS OF SEPTEMBER 16, 1999

         1. Recitals. On February 2, 1982, Storage Technology Corporation, a
Delaware corporation (together with its Subsidiary Corporations, hereinafter
referred to, unless the context otherwise requires, as the "Company"),
established the Storage Technology Corporation 1982 Employee Stock Purchase
Plan. Such plan was subsequently amended and restated by the Board of Directors
(the "Board") on June 15, 1987 and renamed the Storage Technology Corporation
1987 Employee Stock Purchase Plan. Under the provisions of Paragraph 19, the
Company reserved the power, through its Board of Directors, to amend the plan
from time to time, subject in certain instances to approval of the Company's
stockholders. Pursuant to that power, the plan was amended and restated in its
entirety on December 14, 1995 and was approved by the stockholders of the
Company on May 30, 1996. The plan was further amended on September 23, 1997 and
December 19, 1997, and these amendments were approved by the stockholders of the
Company on May 21, 1998. The plan was further amended on September 16, 1999, and
is effective as of that date. (Shareholder approval was not required for the
September 16, 1999 amendments.) The Storage Technology Corporation 1987 Employee
Stock Purchase Plan, as amended and restated through September 16, 1999, is
referred to as the "1987 Plan or the "Plan".

         2. Purposes. The 1987 Plan is intended to provide a method whereby
employees of the Company will have an opportunity to acquire a proprietary
interest in the Company through the purchase of shares of the $.10 par value
voting Common Stock of the Company (the "Common Stock"). It is the intention of
the Company to have the Plan qualify as an "employee stock purchase plan" under
Section 423 of the Internal Revenue Code of 1986, as amended from time to time
(the "Code"). The provisions of the Plan shall, accordingly, be construed so as
to extend and limit participation in a manner consistent with the requirements
of that section of the Code.

         3. Definitions.

                  (a) "Account" means an Employee's interest in the Segregated
Account based on the contributions made thereto and the interest earned thereon.

                  (b) "Base Pay" means, at the Employee's election, either: (i)
an Employee's rate of base salary (before deduction for contributions to plans
maintained pursuant to Sections 401(k) and 125 of the Code) in effect during the
Offering Period, but EXCLUDING payments for overtime, shift premium, incentive
compensation, bonuses, and other similar



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payments; or (ii) Employee's rate of base salary (before deduction for
contributions to plans maintained pursuant to Sections 401(k) and 125 of the
Code) in effect during the Offering Period, EXCLUDING payments for overtime,
shift premium, incentive compensation, bonuses, and other similar payments, but
INCLUDING all payments for bonuses, incentive compensation and various forms of
commissions. Base Pay shall also include payments for short-term disability.

                  (c) "Committee" means the Compensation Committee of the
Company's Board of Directors or such other committee as is designated by the
Board of Directors to administer the Plan.

                  (d) "Employee" means any person who is a Regular Employee (per
CP-3-3-14) customarily employed for more than 20 hours per week and more than
five months in a calendar year by Storage Technology Corporation or any
Subsidiary Corporation.

                  (e) "Offering Commencement Date" shall mean January 1, 1991
and each following November 1 and May 1 thereafter, unless otherwise specified
by the Committee.

                  (f) "Offering Periods" shall mean the period commencing
January 1, 1991 and ending October 31, 1991 and thereafter the periods
commencing each November 1 and May 1 and ending on the next following April 30
and October 31, respectively. The duration of Offering Periods may be changed
pursuant to Paragraphs 5 and 21 of this Plan.

                  (g) "Offering Termination Date" shall mean October 31, 1991
and each following April 30 and October 31 thereafter, unless otherwise
specified by the Committee.

                  (h) "Segregated Accounts" shall mean the depository accounts
established by the Company and by Subsidiary Corporations for collection of
Employee contributions to the Plan.

                  (i) "Subsidiary Corporation" shall mean any present or future
corporation which (i) would be a subsidiary corporation with respect to the
Company as that term is defined in Section 425 of the Code, and (ii) is
designated as a participant in the Plan by the Committee described in Paragraph
14.

         4. Eligibility

                  (a) Participation in the Plan is completely voluntary. An
Employee will be eligible to become a participant in each Offering Period if
employed by the Company on or before 15 days prior to the applicable Offering
Commencement Date.



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                  (b) Any provision of the Plan to the contrary notwithstanding,
no Employee shall be granted an option under the Plan:

                           (i) if, immediately after the grant, such Employee
         would own stock, and/or hold outstanding options to purchase stock,
         possessing 5% or more of the total combined voting power or value of
         all classes of stock of the Company or of any Subsidiary Corporation
         (for purposes of this Paragraph the rules of Section 425(d) of the Code
         shall apply in determining stock ownership of any Employee); or

                           (ii) if such option would permit his or her rights to
         purchase stock under all employee stock purchase plans of the Company
         and its Subsidiary Corporations to accrue at a rate that exceeds
         $25,000 of the fair market value of the stock (determined at the time
         each option is granted) for each calendar year in which such option is
         outstanding; or

                           (iii) for shares in excess of 25,000 in respect of
         any Offering Period, provided that this limitation is subject to
         increase or decrease by the Committee prior to the commencement of any
         Offering Period in respect of such Offering Period.

         5. Plan Offerings.

                  (a) The Plan is authorized to issue a total of 12,200,000
shares of Common Stock.

                  (b) The Plan will be implemented by consecutive Offering
Periods, with a new Offering Period commencing on each Offering Commencement
Date and ending on the next Offering Termination Date, or on such other dates as
the Committee shall determine prior to the commencement of the relevant Offering
Period, and continuing until terminated in accordance with Paragraph 19 hereof.
The Committee shall have the power to change the duration of Offering Periods
(including the commencement and termination dates thereof) with respect to
future offerings without stockholder approval if such change is announced at
least five (5) days prior to the scheduled beginning of the first Offering
Period to be affected.

                  (c) The Committee may determine in its sole discretion from
time to time to fix a maximum number of shares of Common Stock of the Company,
including any unsold balances from earlier Offering Periods (subject to
adjustment upon changes in the capitalization of the Company in accordance with
Paragraph 18 hereof) that shall be issued during any one Offering Period. If the
Committee fixes a maximum number of shares per Offering Period, the maximum
number of shares to be issued in respect of any Offering



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Period may from time to time be increased or decreased by the Committee prior to
the commencement of the affected Offering Period within the limits of the total
shares then available under the Plan.

                  (d) Participation in any Offering Period under the Plan shall
neither limit, nor require, participation in any other Offering Period (except
as set forth in paragraphs 4(b)(i) and 4(b)(ii) hereof).

         6. Participation.

                  (a) An eligible Employee may become a participant by enrolling
and authorizing payroll deductions on an Interactive Voice Response system
("IVR") in such manner as is prescribed by the Company or, if such Employee does
not have access to IVR, by completing an authorization for payroll deduction on
the form provided by the Company and filing it with the department designated by
the Company or the designated country coordinator by the deadline established by
the Company, which must precede the first day of the Offering Period for which
the participant enrolls.

                  (b) Payroll deductions for a participant shall commence on the
applicable Offering Commencement Date when an authorization for a payroll
deduction becomes effective and shall end on the Offering Termination Date of
the Offering Period to which such authorization is applicable unless sooner
terminated by the participant as provided in Paragraph 11.

         7. Payroll Deductions.

                  (a) At the time a participant enrolls and authorizes payroll
deductions, the participant shall elect to have deductions made from his or her
Base Pay and deposited in a Segregated Account during the time the Employee is a
participant in an Offering Period. Deductions can be made at the rate of 1, 2,
3, 4, 5, 6, 7, 8, 9, or 10% of Base Pay.

                  (b) All payroll deductions made for a participant shall be
transferred to a Segregated Account as soon as practicable. For administrative
convenience, the Company may offset amounts advanced by the Company to pay
participant withdrawals pursuant to Paragraph 11 against amounts of payroll
deductions otherwise payable into the Segregated Account. A participant may not
make any separate cash payments into the Segregated Account. The Company shall
maintain appropriate accounting records to reflect at all times the interest and
total deductions of all participants in the Segregated Account.

                  (c) A participant may discontinue participation in the Plan as
provided in Paragraph 11, but no other change can be made during an Offering
Period and, specifically, a participant may not alter the rate of payroll
deductions for that Offering Period.



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         8. Terms and Conditions of Options.

                  (a) On the applicable Offering Commencement Date, when a
participant's authorization for a payroll deduction becomes effective, the
participant shall be deemed to have been granted an option to purchase a maximum
number of shares of Common Stock, subject to the limitations pursuant to
Paragraph 4(b) above, equal to the lesser of: (a) the Option Price (as defined
below) divided into the Employee's total deductions under the Plan in respect of
the Offering Period or (b) the Employee's pro-rata share of all shares available
for issuance under the Plan for that Offering Period, determined pursuant to
Paragraph 13, below.

                  (b) The option price per share (hereinafter "Option Price") of
Common Stock purchased with payroll deductions made during each Offering Period
shall be the lesser of:

                           (i) 85% of the closing price per share of the Common
         Stock as quoted in The Wall Street Journal for the applicable Offering
         Commencement Date (or on the next business date on which shares of the
         Common Stock shall be traded on the New York Stock Exchange in the
         event that no shares of the Common Stock shall have been traded on the
         Offering Commencement Date); or

                           (ii) 85% of the closing price per share of the Common
         Stock as quoted in The Wall Street Journal for the applicable Offering
         Termination Date (or for the next preceding business date on which
         shares of the Common Stock shall be traded on the New York Stock
         Exchange in the event that no shares of the Common Stock shall have
         been traded on the Offering Termination Date).

                  (c) The Committee may determine in its sole discretion from
time to time to issue fractional shares under the Plan. If the Committee
determines not to issue fractional shares, any accumulated payroll deductions
that would have been used to purchase fractional shares shall be (i)
automatically credited to each participant's Account and applied towards his or
her option to purchase shares in the next successive Offering Period, or (ii)
returned to each participant promptly following the termination of the Offering
Period, as may be determined by the Committee. Any accumulated payroll
deductions that are in excess of the limitations of Paragraph 8(a), together
with any net income of the Segregated Account allocable to each participant, and
the amount referenced in item (ii) above, shall be returned to each participant
promptly following the termination of an Offering Period.



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         9. Exercise of Option. Unless a participant withdraws in accordance
with Paragraph 11, his or her option to purchase Common Stock with payroll
deductions made during any Offering Period will be deemed to have been exercised
automatically on the applicable Offering Termination Date, for the purchase of
the number of full shares of Common Stock that the accumulated payroll
deductions will purchase at the applicable Option Price (but not in excess of
the number of shares for which options have been granted to the participant
pursuant to Paragraph 8(a)), and any excess in his or her Account at that time
will be returned to the participant, together with any net income of the
Segregated Account allocable to his or her Account, as provided in Paragraph 13.

         10. Delivery. As promptly as practicable after the Offering Termination
Date of each Offering Period, the Company will deliver to a broker designated by
the Committee to hold shares for the benefit of the participants the shares of
Common Stock purchased upon the exercise of the participant's option. As may be
determined by the Committee in its sole discretion from time to time, such
shares shall be delivered by physical certificates or by means of a book entry
system. A participant may instruct any such designated broker to sell shares
purchased upon exercise of the participant's option at any time, subject to
applicable securities laws; provided, that the Committee (i) may restrict a
participant's right to transfer shares to another brokerage, institution, or any
other person (including the participant) during the initial 24 months following
the Offering Commencement Date in which the shares were purchased, and (ii) may
determine that, for purposes of Section 423(b)(8)(B) of the Internal Revenue
Code, the shares were sold if a participant transfers shares to another
brokerage or financial institution, or any other person (including the
participant) during the initial 24 months following the Offering Commencement
Date in which shares were purchased.

         11. Withdrawal and Termination.

                  (a) Prior to the 15th day of the month before the applicable
Offering Termination Date, any participant may withdraw payroll deductions and
net earnings thereon credited to the participant by following the procedures
specified by the Company for effecting a withdrawal on the IVR system or, if the
participant does not have access to IVR, by giving written notice of withdrawal
to the department designated by the Company or the designated country
coordinator. As promptly as practical after the participant's withdrawal, the
payment to the participant of all the participant's payroll deductions credited
to his or her account, together with any net earnings of the Segregated Account
allocable to the participant's Account shall be made. No further payroll
deductions for such participant will be made during such Offering Period. The
Company may, for administrative convenience, elect to pay to participants (or
beneficiaries) the amount of any withdrawals and earnings thereon and may then
offset the amount of any such payments against payroll deductions otherwise
payable to the Segregated Account. The Company may, at its option, treat any
attempt to borrow by a participant on the security of the accumulated payroll
deductions allocated to the participant's Account as an election under this
Paragraph 11(a) to withdraw such amounts from the Segregated Account.



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                  (b) A participant's withdrawal from any Offering Period will
not have any effect upon eligibility to participate in any subsequent Offering
Period or in any similar plan that may hereafter be adopted by the Company.

                  (c) Upon termination of the participant's employment with the
Company for any reason (including retirement but excluding death or, in certain
cases, disability while in the employ of the Company) on or prior to the last
day of the last full payroll period immediately preceding an Offering
Termination Date, the payroll deductions credited to the participant, together
with any net earnings of the Segregated Account allocable to his or her Account,
will be returned to the participant, or, in the case of a participant's death
subsequent to the termination of employment, to the person or persons entitled
thereto under Paragraph 15. For purposes of the Plan, a participant shall be
considered disabled if the Company determines that the participant is unable to
perform the usual and customary requirements of his or her job with the Company
and will be unable to do so for at least six months; provided, however, that
such determination is subject to review by the Committee at its discretion.

                  (d) Upon termination of the participant's employment because
of death or disability prior to the Offering Termination Date, the participant
or the participant's beneficiary (as defined in Paragraph 15) shall have the
right to elect, by written notice given to the Company's General Counsel prior
to the expiration of the period of 90 days commencing on the date of death or
disability of the participant, and prior to the Offering Termination Date,
either

                           (i) to withdraw all of the payroll deductions
         credited to the participant, together with any net earnings of the
         Segregated Account allocable to his or her Account, or

                           (ii) to exercise the participant's option to purchase
         of Common Stock for the then current Offering Period on the Offering
         Termination Date for the purchase of the number of full shares of
         Common Stock that the amount allocated to the participant's Account at
         the date of the participant's death or disability will purchase at the
         applicable Option Price, and any excess credited to such Account will
         be returned to said participant or his or her beneficiary.

         In the event that no such written notice of election shall be duly
received by the office of the Company's General Counsel within the required time
period, the participant or beneficiary shall automatically be deemed to have
elected to withdraw the payroll deductions credited to the participant, together
with the net earnings of the Segregated Account allocable



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to his or her Account at the date of the participant's death or disability, and
the same will be paid promptly to said participant or beneficiary.
Notwithstanding the foregoing, if a participant's employment with the Company
and any Subsidiary Corporation terminates because of disability more than three
months prior to the Offering Termination Date, the provisions of this Paragraph
11(d) shall not apply and the provisions of Paragraph 11(c) shall apply to such
participant.

         12. Income and Accounting.

                  (a) Separate accounts shall not be established by the Company
for Employees who participate in the Plan. The Employee's payroll deductions
shall be transferred to the Segregated Account as soon as practical after each
pay period and credited to the participant.

                  (b) Each participant shall share proportionately in the income
and expense of the Segregated Account and any net income shall be taxable to the
participant, who shall be responsible for paying any income or other taxes
applicable thereto.

         13. Stock.

                  (a) If the Committee, in its sole discretion, fixes a maximum
number of shares that shall be made available for sale under the Plan during any
Offering Period, such number of shares may be adjusted if less than the number
of shares that may be specified by the Committee with respect to any Offering
Period are purchased during any Offering Period. In such event, the number of
shares not purchased in the Offering Period may be carried over and made
available for sale under the Plan during any subsequent Offering Period. If the
total number of shares subject to options that would otherwise be exercised on
any Offering Termination Date in accordance with Paragraph 9 exceeds the maximum
number of shares available for sale, subject to adjustment as aforesaid, the
Company shall make a pro rata allocation of the shares available for delivery
and distribution in as nearly a uniform manner as shall be practicable and as it
shall determine to be equitable, and the balance of payroll deductions credited
to each participant, together with the net earnings of the Segregated Account
allocable thereto, shall be returned to him or her as promptly as possible.

                  (b) A participant will have no interest in Common Stock
covered by the participant's option until such option has been exercised.
Participants in the Plan shall have no rights as stockholders with respect to
any shares covered by the Plan until the date of issue of a stock certificate to
him or her for such shares. Except as otherwise expressly provided in the Plan
or in the corporate action relating to such event, no adjustment shall be made
for dividends or other rights for which the record date is prior to the date
such stock certificate is issued.



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                  (c) Common Stock to be delivered to a participant under the
Plan will be registered in the name of the participant.

                  (d) The Board of Directors may, in its discretion, require as
conditions to the exercise of any option that the shares of Common Stock
reserved for issuance upon the exercise of the option shall have been duly
listed, upon official notice of issuance, upon the New York Stock Exchange, and
that either

                           (i) a Registration Statement under the Securities Act
         of 1933, as amended, with respect to said shares shall have become
         effective, or

                           (ii) the participant shall have represented in form
         and substance satisfactory to the Company that it is the participant's
         intention to purchase for investment the shares being purchased under
         such option.

         14. Administration. The Plan shall be administered by the Committee.
The interpretation and construction of any provision of the Plan or any
Segregated Account agreement and the adoption of rules and regulations for
administering the Plan shall be made by the Committee, subject, however, at all
times to the final concurrence of the Board of Directors of the Company.
Determinations made by the Committee and approved by the Board of Directors with
respect to any matter or provision contained in the Plan shall be final,
conclusive and binding upon the Company and upon all participants, their heirs
or legal representatives. Any rules, regulations or interpretations adopted by
the Committee shall remain in full force and effect unless and until altered,
amended, or repealed by the Committee or the Board of Directors.

         15. Designation of Beneficiary. A participant may file with the
Company, pursuant to rules adopted by the Committee, a written designation of a
beneficiary who is to receive any Common Stock and/or cash pursuant to the
provisions of the Plan in the event of the participant's death. Such designation
of beneficiary may be changed by the participant at any time by written notice.
Upon the death of a participant and upon receipt by the Company of proof of the
identity and existence at the participant's death of a beneficiary validly
designated by him under the Plan, the Company shall deliver such Common Stock to
such beneficiary and/or pay any cash in the participant's Account in the
Segregated Account to the beneficiary, as may be required under the provisions
of Paragraph 11(d). In the event of the death of a participant and in the
absence of a beneficiary validly designated under the Plan who is living at the
time



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of such participant's death, the Company shall cause such cash to be paid to the
person or persons or the entity duly designated by the participant, as shown on
the Company's records, as his or her beneficiary for the proceeds of Company
paid life insurance. In the absence of such a beneficiary who is living at the
time of the participant's death, the Company shall cause such cash to be paid to
the executor or administrator of the estate of the participant, or if no such
executor or administrator of the estate has been appointed (to the knowledge of
the Company), the Company, in its discretion, may cause such cash to be paid to
the spouse or to any one or more dependents of the participant as the Company
may designate. No beneficiary shall, prior to the death of the participant by
whom he or she has been designated, acquire any interest in the Common Stock or
in amounts credited to the participant's Account.

         16. Transferability. Neither payroll deductions credited to a
participant, nor earnings thereon, nor any rights with regard to the exercise of
an option or to receive Common Stock under the Plan may be assigned,
transferred, pledged, or otherwise disposed of in any way by the participant
otherwise than by will or the laws of descent and distribution. Any such
attempted assignment, transfer, pledge or other disposition shall be without
effect, except that the Company may treat such act as an election to withdraw
funds in accordance with Paragraph 11.

         17. Ownership of ESPP Assets. All contributions paid into Segregated
Accounts shall be the property of the respective participants in the Plan and
the Company shall have no interest in such amounts while held in the Segregated
Account.

         18. Effect of Changes in Capital Structure. If the outstanding shares
of Common Stock are changed into or exchanged for a different number or kind of
shares or other securities of the Company by reason of any recapitalization,
reclassification, stock split, stock dividend, combination, or subdivision, or
if the Company takes any other action of a similar nature affecting such Common
Stock (excluding, however, any reorganization under the United States Bankruptcy
Code), then the number and class of shares of Common Stock that may thereafter
be optioned, or the rights assigned thereto (in the aggregate and to any
participant), shall be adjusted accordingly and, in the case of each option
outstanding at the time of any such action, the number and class of shares that
may thereafter be purchased pursuant to such option and the Option Price shall
be adjusted, in each case to such extent and in such manner, if at all, as may
be determined by the Board upon the recommendations of the Committee, with the
approval of independent public accountants and counsel, to be necessary to
preserve unimpaired the rights of the holder of such option.

         19. Amendment or Termination. The Board of Directors of the Company may
at any time terminate or amend the Plan. No such termination can affect options
previously granted, nor may an amendment make any change in any option
theretofore granted without prior approval of the stockholders of the Company if
such approval is required under the laws or regulations administered by the U.S.
Treasury (including Section 423 of the Code), the Securities and Exchange
Commission (including Rule 16b-3), any other agency of the U.S. Government, or
the New York Stock Exchange, or any other exchange or system on which the
Company's stock is then registered or traded.



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         20. Notices. All notices or other communications by a participant to
the Company under or in connection with the Plan shall be deemed to have been
duly given when received by the General Counsel of the Company.

         21. Dissolution, Merger or Asset Sale.

                  (a) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Offering Period shall terminate
immediately prior to the consummation of such proposed action, unless otherwise
provided by the Board.

                  (b) Merger or Asset Sale. In the event of a proposed sale of
all or substantially all of the assets of the Company, or the merger of the
Company with or into another corporation, each option under the Plan shall be
assumed or an equivalent option shall be substituted by such successor
corporation or a parent or subsidiary of such successor corporation, unless the
Board determines, in the exercise of its sole discretion and in lieu of such
assumption or substitution, to shorten the Offering Period then in progress by
setting a new Offering Termination Date (the "New Offering Termination Date") or
to cancel each outstanding right to purchase and refund all sums collected from
participants during the Offering Period then in progress. If the Board shortens
the Offering Period then in progress in lieu of assumption or substitution in
the event of a merger or sale of assets, the Board shall notify each participant
in writing, at least ten (10) business days prior to the New Termination Date,
that the Offering Termination Date for the option held by the participant has
been changed to the New Offering Termination Date and that such option shall be
exercised automatically on the New Offering Termination Date, unless prior to
such date the participant has withdrawn from the Offering Period as provided in
Paragraph 10 hereof. For purposes of this paragraph, an option granted under the
Plan shall be deemed to be assumed if, following the sale of assets or merger,
the option confers the right to purchase, for each share of option stock subject
to the option immediately prior to the sale of assets or merger, the
consideration (whether stock, cash or other securities or property) received in
the sale of assets or merger by holders of Common Stock for each share of Common
Stock held on the effective date of the transaction (and if such holders were
offered a choice of consideration, the type of consideration chosen by the
holders of a majority of the outstanding shares of Common Stock); provided,
however, that if such consideration received in the sale of assets or merger was
not solely common stock of the successor corporation or its parent (as defined
in Section 424(e) of the Code), the Board may, with the consent of the successor
corporation, provide for the consideration to be received upon exercise of the
option to be solely common stock of the successor corporation or its parent
equal in fair market value to the per share consideration received by holders of
Common Stock and the sale of assets or merger.



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         22. Effective Date of Offering Periods. Offerings may commence under
the Plan prior to approval by the stockholders of any amendments or restatements
under Paragraph 19 above, but no Common Stock requiring stockholder approval may
be purchased hereunder unless and until the requisite stockholder approval has
been received.



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