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                                                                   EXHIBIT 10.12

December 31, 1999




Mr. James D. Bartlett
6408 Willow Springs Drive
Morrison,  CO   80465

RE: SEPARATION AGREEMENT


Dear Jim:

It is acknowledged that you will be involuntarily terminated from StorageTek
effective December 31, 1999 ("Termination Date"). This letter will confirm our
agreement concerning the termination of your employment with Storage Technology
Corporation ("StorageTek" or the "Company") as Corporate Vice President, and
Chief Marketing Officer. In that regard, this letter will define the terms of
your severance under this Separation Agreement (the "Separation Agreement").
This Separation Agreement supersedes all previous oral and written agreements
regarding your employment with StorageTek, provided however that the terms and
conditions of your Corporate Officer Employment Agreement dated October 13, 1999
(the "Employment Agreement"), to the degree that they do not conflict with the
terms and conditions of this Separation Agreement, shall remain in full force
and effect.

         SEPARATION: The Company will pay, within 30 days of the Termination
         Date, a separation payment equal to the amounts set forth in Sections
         5(a) and 5(c) of the Employment Agreement, including: one year's salary
         ($225,000.00), and one year's target MBO bonus for 1999 ($100,000.00).
         Your stock options will vest upon termination and the Company's right
         of repurchase on restricted stock will be void. Pursuant to the terms
         of StorageTek's Stock Option Plan, you will have 90 days from the
         Termination Date to exercise these options.

         In addition to the consideration recited above, the Company will (1)
         forgive all moneys that may be owed under the terms of your relocation
         package and sign-on bonus, and (2) the Promissory Note dated June 10,
         1999 including the gross up of any imputed interest accrued through the
         Termination Date. The payments recited in this Separation Agreement are
         contingent upon your execution and delivery to the Company a Settlement
         and Release Agreement substantially in the form attached as Exhibit A
         to your Employment Agreement.



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    James D. Bartlett
    December 31, 1999
    Page  -2-



         NO ADVERSE COMMENT: You agree that during your employment with the
         Company through the Termination Date and for at least one year
         following the Termination Date, you will not, except as specifically
         required by law or court process or consented to in writing by the
         Company, (a) communicate to any person or entity any adverse
         information, written or oral, concerning the Company, its officers,
         directors, employees, attorneys, agents or advisers (including any
         communication concerning information that related to the business,
         operations, prospects or affairs of the Company or any of its
         subsidiaries or affiliates) under the circumstances in which there is a
         reasonable possibility that such information might be publicly reported
         or disclosed or otherwise made available to third parties (regardless
         of whether the communication of such information is intended to have or
         cause that result is within your control), or (b) provide to any person
         (other than your attorney or accountant) or entity any information that
         concerns or related to the negotiations or circumstances leading to the
         execution of this Separation Agreement.

         NON-SOLICITATION: Per the terms of Section 8 of your Employment
         Agreement, you confirm that during the two-year period commencing with
         the Termination Date, you will not, directly, or indirectly, hire,
         solicit, or encourage any then-current Company employees to apply for
         employment with any person or entity (a) with which you are (or intend
         to be) employed, (b) by whom you or an entity in which you are employed
         or have a financial interest is engaged as a consultant, recruited,
         independent contractor or otherwise, or (c) in which you further
         covenant and agree that you will not provide to any other person or
         entity the names of or references on any person who is then employed by
         the Company.

         NON-COMPETE: Per the terms of Section 8 of your Employment Agreement,
         you confirm that for a period of one year from the Termination Date
         that you will not, either directly or indirectly, engage in any
         activity in competition with any product or service of the Company
         (said competitive activities to be determined and identified at the
         reasonable discretion of the Company), or harmful or contrary to the
         best interest of the Company, including accepting employment with or
         serving as a consultant to any entity that is in competition with the
         Company. In particular, you agree that competitor companies include,
         ATL/Quantum, Breece Hill, EMC, Hewlett-Packard, Sun Microsystems and
         IBM. However, with regard to IBM and HP, you may seek employment with
         those companies in their: (i) PC business units, (ii) consumer sales
         activities, (iii) printer operations, or (iv) such similar product
         areas or business units as StorageTek shall approve in writing, such
         approval not to be unreasonably withheld or delayed.

         COMPANY RELEASE: The Company hereby irrevocably and unconditionally
         releases and discharges you and your heirs, successors, and assigns
         (separately and collectively, "releasees"), jointly and individually,
         from any and all claims, known or unknown, which it, its past and
         present subsidiaries, divisions, officers, directors, agents,
         employees, successors, and assigns have or may have against releasees
         and any and all liability which releasees may have to it, whether
         denominated claims,



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    James D. Bartlett
    December 31, 1999
    Page  -3-

         demands, causes of action, obligations, damages or liabilities arising
         from any and all bases, however denominated, provided, however, that
         this release does not affect any claims which are based on releasees'
         willful acts, gross negligence or dishonesty in the performance of
         duties as an employee of the Company, nor any claims which may arise
         after the execution of this Agreement. The Company further agrees that
         it will not file or permit to be filed on its behalf any claim against
         you which is released hereby.

         NONDISCLOSURE: Unless otherwise required to do so by law, subpoena or
         court order, neither party will in any way communicate or discuss the
         terms of this Separation Agreement or the circumstances of your
         termination with any person, other than your attorneys. You understand
         that this nondisclosure provision applies particularly to current and
         former employees of the Company and the Company's customers, clients
         and vendors.

This Separation Agreement, shall be deemed for purposes of the Older Workers
Benefits Protection Act to have been delivered to you for your consideration on
January 12, 2000. You have 21 days from that date to decide whether or not to
accept this agreement. If you accept this agreement, you will then have seven
days from the date you sign this agreement and deliver an executed copy to the
Company during seven day period you may revoke your acceptance by notifying the
Company in writing of your desire to do so. No amounts otherwise due to you
under this Separation Agreement will be paid to you until the expiration of that
seven day revocation period.

Please sign both copies of this letter below, and the attached Settlement and
Release, indicating your acceptance, and return one copy for our files.


Accepted and Agreed:                           Very truly yours,
                                            STORAGE TECHNOLOGY CORP.




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JAMES D. BARTLETT                           Victor Perez
                                            Executive Vice President,
                                            Chief Operating Officer



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                                    EXHIBIT A

                             SETTLEMENT AND RELEASE


1.      In exchange for payment of salary (in the amount of $225,000.00) and
        bonus (in the amount of $100,000.00) to James D. Bartlett ("Employee"),
        by Storage Technology Corporation ("Company") and other good and
        valuable consideration, including but not limited to, forgiveness for
        advances for relocation, sign-on bonus and cancellation of the
        Promissory Note of June 10, 1999, Employee hereby irrevocably and
        unconditionally releases and discharges the Company, its past and
        present subsidiaries, divisions, officers, directors, agents, employees,
        successors, and assigns (separately and collectively, "releasees")
        jointly and individually, from any and all claims, known or unknown,
        which he/she, his/her heirs, successors or assigns have or may have
        against releasees and any and all liability which releasees may have to
        him/her whether denominated claims, demands, causes of action,
        obligations, damages, or liabilities arising from any and all bases,
        however denominated, including but not limited to, any claims of
        discrimination under the Age Discrimination in Employment Act ("ADEA"),
        the Older Workers Benefit Protection Act, the Rehabilitation Act, the
        Family Medical Leave Act, the Americans with Disabilities Act, Title VII
        of the Civil Rights Act of 1964, the Civil Rights Act of 1991 or any
        federal or state civil rights act, claims for wrongful discharge, breach
        of contract, or for damages under any other federal, state or local law,
        rule or regulation, or common law under any theory; provided, however,
        that this release does not affect (1) any claims for benefits which have
        vested or shall vest on or before the effective date of this Settlement
        and Release ("Release") under any of the Company's benefit plans; (2)
        any claims for indemnification for acts of Employee which have occurred
        or may occur as an officer or employee of the Company; or (3) any claims
        which may arise after the execution of this Release. This release
        specifically excepts any claim Employee may wish to make for
        unemployment compensation, and the Company agrees not to contest any
        claim made by Employee for unemployment compensation. This release is
        for any relief, no matter how denominated, including, but not limited
        to, back pay, front pay, compensatory damages, punitive damages, or
        damages for pain and suffering. Employee further agrees that he will not
        file or permit to be filed on his behalf any such claim, will not permit
        himself to be a member of any class seeking relief against the releasees
        and will not counsel or assist in the prosecution of claims against the
        releasees, whether those claims are on behalf of himself or others,
        unless he is under a court order to do so.

2.      Employee agrees that by signing this Release, he is giving up the right
        to sue for age discrimination, and that under this Release Employee
        shall receive consideration to which he is not otherwise entitled, and
        would not receive but for his release of rights under the ADEA. Employee
        has up to twenty-one (21) days after delivery of this Release to
        consider whether to sign this Release. Employee agrees that, after he
        has signed and delivered this Release to the Company, this Release will
        not be effective or enforceable until the end of a seven (7) day
        revocation period beginning the day after the Employee signs this
        Release, and that Employee will not receive the severance payment due
        under the Employment Agreement until this seven-day period has expired.
        During this seven-day period, Employee may revoke this Release, without
        reason and in his sole judgment, but he may do so only by delivering a
        written statement of revocation to the Company to the attention of
        General Counsel. If the Company does



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        not receive a written statement of revocation from Employee by the end
        of the revocation period, then this Release will become legally
        enforceable and Employee may not thereafter revoke this Release.

3.      Employee agrees that this Release shall be governed by federal law and
        the internal laws of the State of Colorado, irrespective of the choice
        of law rules of any state.


ACKNOWLEDGMENT:

Employee's signature below acknowledges that he has read this document fully,
that he understands and agrees to its contents, that he understands that it is a
legally binding document, and that he has been advised to consult a lawyer of
his choosing before signing this Release, and has had the opportunity to do so.



--------------------------                  -----------------------------------
Date                                                JAMES D. BARTLETT





This Release presented to Employee on                           .
                                      --------------------------