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                                                                   EXHIBIT 10.12

           GENERAL INSTRUMENT CORPORATION DEFERRED COMPENSATION PLAN

ARTICLE 1--INTRODUCTION

1.1 PURPOSE OF PLAN--AMENDMENT AND RESTATEMENT

    NextLevel Systems, Inc. adopted the NextLevel Deferred Compensation Plan
("NextLevel Plan") effective July 1, 1997. Effective as of February 2, 1998,
NextLevel Systems, Inc. changed its name to General Instrument Corporation. This
General Instrument Corporation Deferred Compensation Plan is a successor to the
NextLevel Plan. The Plan provides a means by which certain employees may elect
to defer receipt of designated percentages or amounts of their Compensation.

    Effective as of the distribution by General Instrument Corporation ("Old
GI") of all its shares of stock of NextLevel Systems, Inc. (the "Spinoff"), the
NextLevel Plan assumed the liabilities from the GI Deferred Compensation Plan
("Old GI Plan") with respect to participants in the Old GI Plan as of the date
of the Spinoff whose employment after the Spinoff was with the business of
NextLevel Systems, Inc. As of the Spinoff, assets were to be transferred from
the trust maintained in connection with the Old GI Plan to the Trust maintained
in connection with the Plan, in an amount equal to the liabilities transferred
from the Old GI Plan to the Plan. Effective as of February 2, 1998, the
liabilities of the NextLevel Plan are transferred to and assumed by the Plan.

1.2 STATUS OF PLAN

    The Plan is intended to be "a plan which is unfunded and is maintained by an
employer primarily for the purpose of providing deferred compensation for a
select group of management or highly compensated employees" within the meaning
of Sections 201(2), 301(a)(3) and 401(a)(1) of the Employee Retirement Income
Security Act of 1974 ("ERISA"), and shall be interpreted and administered to the
extent possible in a manner consistent with that intent.

ARTICLE 2--DEFINITIONS

    Wherever used herein, the following terms have the meanings set forth below,
unless a different meaning is clearly required by the context:

2.1 ACCOUNT means, for each Participant, the bookkeeping account established for
his or her benefit under Section 5.1.

2.2 CHANGE OF CONTROL has the meaning set forth in the NextLevel Systems, Inc.
1997 Long-Term Incentive Plan (now renamed the General Instrument Corporation
1997 Long-Term Incentive Plan).

2.3 CODE means the Internal Revenue Code of 1986, as amended from time to time.
Reference to any section or subsection of the Code includes reference to any
comparable or succeeding provisions of any legislation which amends, supplements
or replaces such section or subsection.

2.4 COMPANY means on and after February 2, 1998, General Instrument Corporation
(and prior to February 2, 1998, NextLevel Systems, Inc.) and any successor to
all or a major portion of the Company's assets or business which assumes the
obligations of the Company, and each other entity that is affiliated with the
Company which adopts the Plan with the consent of the Company. With respect to
any Participant, the "Company" shall mean the entity by which he is employed.

2.5 COMPENSATION means base salary payable to a Participant by the Company or an
affiliate, and any bonuses earned by a Participant under the Company's annual
management incentive plan.

2.6 EFFECTIVE DATE of this amendment and restatement is February 2, 1998. The
Plan was originally effective July 1, 1997.

2.7 ELECTION FORM means the participation election form as approved and
prescribed by the Plan Administrator.
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2.8 ELECTIVE DEFERRAL means the portion of Compensation which is deferred by a
Participant under Section 4.1.

2.9 ELIGIBLE EMPLOYEE means each employee of the Company who is at a salary
level of Grade 16 or higher.

2.10 ERISA MEANS the Employee Retirement Income Security Act of 1974, as amended
from time to time. Reference to any section or subsection of ERISA includes
reference to any comparable or succeeding provisions of any legislation which
amends, supplements or replaces such section or subsection.

2.11 INSOLVENT means either (i) the Company is unable to pay its debts as they
become due, or (ii) the Company is subject to a pending proceeding as a debtor
under the United States Bankruptcy Code.

2.12 PARTICIPANT means any individual who participates in the Plan in accordance
with Article 3.

2.13 PLAN means the General Instrument Corporation Deferred Compensation Plan as
set forth herein and all amendments thereto.

2.14 PLAN ADMINISTRATOR means the person, persons or entity designated by
General Instrument Corporation from time to time to administer the Plan and to
serve as the agent for the Company with respect to the Trust as contemplated by
the agreement establishing the Trust. If no such person or entity is so serving
at any time, General Instrument Corporation shall be the Plan Administrator.

2.15 PLAN YEAR means the 12-month period beginning January l and ending December
31.

2.16 TOTAL AND PERMANENT DISABILITY means the inability of a Participant to
engage in any substantial gainful activity by reason of any medically
determinable physical or mental impairment which can be expected to result in
death or which has lasted or can be expected to last for a continuous period of
not less than 12 months, and the permanence and degree of which shall be
supported by medical evidence satisfactory to the Plan Administrator.

2.17 TRUST means the applicable trust established by General Instrument
Corporation or an affiliate thereof that identifies the Plan as a plan with
respect to which assets are to be held by the Trustee.

2.18 TRUSTEE means the trustee or trustees under the Trust.

ARTICLE 3--PARTICIPATION

3.1 COMMENCEMENT OF PARTICIPATION

    Any individual who elects to defer part of his or her Compensation in
accordance with Section 4.1 shall become a Participant in the Plan as of the
date such deferrals commence in accordance with Section 4.1.

3.2 CONTINUED PARTICIPATION

    A Participant in the Plan shall continue to be a Participant so long as any
amount remains credited to his or her Account.

ARTICLE 4--ELECTIVE DEFERRALS

4.1 ELECTIVE DEFERRALS

    Any individual who becomes an Eligible Employee after June 30, 1997 may, by
completing an Election form and filing it with the Plan Administrator within 30
days after becoming an Eligible Employee, elect to defer a percentage or dollar
amount of one or more payments of Compensation, on such terms as the Plan
Administrator may permit, which are earned and payable to the Participant after
the date on which the

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individual files the Election Form; provided that such Participant may not elect
to defer any part of his or her bonus payable in any Plan Year, after November
15 of the year preceding such Plan Year.

    Any Eligible Employee who has not otherwise initially elected to defer
Compensation in accordance with this paragraph 4.1 may elect to defer a
percentage or dollar amount of one or more payments of Compensation, on such
terms as the Plan Administrator may permit, commencing with Compensation paid in
the next succeeding Plan Year, by completing an Election form, with respect to
base salary, prior to the first day of such succeeding Plan Year, or with
respect to bonus deferral, before November 15 of the year preceding such Plan
Year.

    A Participant may elect to defer only up to 50% of base salary and up to
100% of any bonuses earned under the Company's annual management incentive plan
for any Plan Year. Base salary is determined before giving effect to Elective
Deferrals and other salary reduction amounts which are not included in the
Participant's gross income under Code sections 125, 401(k), 402(h) or 403(b).

    A Participant's Compensation shall be reduced in accordance with the
Participant's election hereunder and amounts deferred hereunder shall be paid by
the Company to the Trust once per month and credited to the Participant's
Account as of the date the amounts are received by the Trustee. Elective
Deferrals shall not be in effect for any Participant during any period in which
such Participant is eligible to receive benefits under the Company's Long Term
Disability policy.

    An election to defer a percentage or dollar amount of Compensation for any
Plan Year shall apply for only such Plan Year. An Eligible Employee must make a
new deferral election as of the first day of any Plan Year by giving written
notice to the Plan Administrator, with respect to base salary deferral, before
such first day or with respect to bonus deferral, before November 15 of the year
preceding such Plan Year (or, in each case, any such earlier date as the Plan
Administrator may prescribe.)

ARTICLE 5--ACCOUNTS

5.1 ACCOUNTS

    The Plan Administrator shall establish a bookkeeping Account for each
Participant reflecting Elective Deferrals made for the Participant's benefit
together with any adjustments for income, gain or loss and any payments from the
Account. The Plan Administrator may cause the Trustee to maintain and invest
separate asset accounts corresponding to each Participant's Account. The Plan
Administrator shall establish sub-accounts for each Participant that has more
than one election in effect under Section 7.1 and such other sub-accounts as are
necessary for the proper administration of the Plan. As of the last business day
of each calendar quarter, the Plan Administrator shall provide the Participant,
as soon as practicable after the end of such quarter, with a statement of his or
her Account reflecting the income, gains and losses (realized and unrealized),
amounts of deferrals, and distributions of such Account since the prior
statement.

5.2 INVESTMENTS

    The assets of the Trust shall be invested in such investments as the Trustee
shall determine. The Trustee may (but is not required to) consider the Company's
or a Participant's investment preferences when investing the assets attributable
to a Participant's Account. A Participant, at the time of making a deferral
election, may designate the rate of return to be credited to his accounts from
among options offered by the Company. A Participant (or the beneficiary or legal
representative of a deceased Participant) may change such designated rate of
return, effective as of the first business day of any calendar quarter, by
filing a written election specifying the change with the Plan Administrator no
later than the fifteenth day of the month preceding the first month of such
calendar quarter. Such designations shall not obligate the Company or the
Trustee to set aside or invest assets designed to provide such rate of return.

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ARTICLE 6--VESTING

6.1 GENERAL

    A Participant shall be immediately vested in, i.e., shall have a
nonforfeitable right to, all Elective Deferrals, and all income and gain
attributable thereto, credited to his or her Account.

ARTICLE 7--PAYMENTS

7.1 ELECTION AS TO TIME AND FORM OF PAYMENT

    A Participant shall elect irrevocably on the Election Form the date at which
the Elective Deferrals (including any earnings attributable thereto) will
commence to be paid to the Participant. Such date must be at least five years
following the date at which such Elective Deferrals commence. The Participant
shall also elect thereon for payments to be paid in either:

     a. a single lump deferrals sum; or

     b. annual installments over a period elected by the Participant up to 10
        years, the amount of each installment to equal the balance of his or her
        Account immediately prior to the installment divided by the number of
        installments remaining to be paid ("Annual Installments").

    Each such election will be effective only for deferrals (including any
earnings or losses attributable thereto) for the Plan Year for which it is made.
Except as provided in Sections 7.2, 7.3, 7.4, or 7.5, payment of a Participant's
Account shall be made in accordance with the Participant's elections under this
Section 7.1.

7.2 CHANGE OF CONTROL

    The Plan will terminate upon a Change of Control. Immediately prior to the
consummation of a transaction resulting in a Change of Control or, if not
possible, as soon as possible following a Change of Control, each Participant
shall be paid his or her entire Account balance in a single lump sum.

7.3 TERMINATION OF EMPLOYMENT PRIOR TO RETIREMENT AGE

    Upon termination of a Participant's employment for any reason including
Total and Permanent Disability, but other than death, prior to the attainment of
the Retirement Age, which is age 55, the Participant's entire Account shall be
paid to the Participant, according to the Participant's irrevocable election on
the Election Form, in a single lump sum as soon as practicable following the end
of the quarter in which such termination occurs (and valued as of the last
business day of such quarter), or in Annual Installments over a period elected
by the Participant up to 10 years, commencing the year immediately following the
year in which such termination occurs (with each distribution valued as of the
last day of the calendar quarter preceding the date of distribution).

7.4 DEATH

    If a Participant dies prior to the complete distribution of his or her
Account, the balance of the Account shall be paid, according to the
Participant's irrevocable election on the Election Form, to the Participant's
designated beneficiary or beneficiaries, in a single lump sum as soon as
practicable following the end of the quarter in which death occurs (and valued
as of the last business day of such quarter), or in Annual Installments over a
period elected by the Participant up to 10 years, commencing the year
immediately following the year in which death occurs (with each distribution
valued as of the last day of the calendar quarter preceding the date of
distribution).

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    Any designation of beneficiary and form of payment to such beneficiary shall
be made by the Participant on a designation/change of beneficiary form filed
with the Plan Administrator and may be changed by the Participant at any time by
filing another designation/change of beneficiary form containing the revised
instructions. If no beneficiary is designated or no designated beneficiary
survives the Participant, payment shall be made to the Participant's surviving
spouse, or, if none, to his or her issue per stirpes, in a single payment. If no
spouse or issue survives the Participant, payment shall be made in a single lump
sum to the Participant's estate.

7.5 UNFORESEEN EMERGENCY

    If a Participant suffers an unforeseen emergency, as defined herein, the
Plan Administrator, in its sole discretion, may pay to the Participant only that
portion, if any, of his or her Account which the Plan Administrator determines
is necessary to satisfy the emergency need, including at the discretion of the
Plan Administrator any amounts necessary to pay any federal, state and local
income taxes reasonably anticipated to result from the distribution.

    A Participant requesting an emergency payment shall apply for the payment in
writing in a form approved by the Plan Administrator and shall provide such
additional information as the Plan Administrator may require. For purposes of
this paragraph, "unforeseen emergency" means an immediate and heavy financial
need resulting from any of the following:

     a. expenses which are not covered by insurance and which the Participant or
        his or her spouse or dependent has incurred as a result of sudden and
        unexpected illness or accident; or

     b. expenses which are not covered by insurance and which the Participant or
        his or her spouse or dependent has incurred or must incur as a result of
        a casualty loss.

7.6 TAXES

    All federal, state and local taxes that the Plan Administrator determines
are required to be withheld from any payments made pursuant to this Article 7
shall be withheld.

7.7 CLAIMS PROCEDURE

    A Participant or beneficiary (a "Claimant") entitled to benefits may file a
claim for such benefits with the Plan Administrator, in such form as permitted
by the Plan Administrator. The claim will be evaluated and a decision rendered
within ninety (90) days, unless special circumstances require an additional
ninety (90) day extension of time.

    A Claimant shall be given written notice of whether the claim is granted or
denied, in whole or in part, including (1) specific reasons for the denial, (2)
references to pertinent Plan provisions on which the denial is based, (3) a
description of any additional material or information necessary to perfect the
claim and explanation as to why necessary, and (4) the Claimant's right to seek
review of the denial.

    If denied, in whole or in part, the Claimant may make a written request for
review of such denial to the Plan Administrator, within 60 days after receipt of
the denial, and may include pertinent documents, issues and comments to aid the
Plan Administrator. The request will be evaluated and a decision rendered within
sixty (60) days, unless special circumstances require an additional sixty (60)
day extension of time. The written decision will specify reasons for the
decision and references to Plan provisions upon which the decision is based.

    A Claimant who fails to file a claim, or submit a request for review of an
initial claim shall have no right to review and shall have no right to bring
action in any court. The denial of the claim shall be final and binding on all
persons for all purposes.

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7.8 SECTION 162(M) LIMITATIONS

    In the event that any amount to be paid pursuant to Section 7.1, 7.3, 7.4 or
7.5 would, in the Company's judgment, result in the non-deductibility, under
Section 162(m) of the Code, of any portion of such Participant's income payable
by or attributable to the Company for the year in which such amount is to be
paid, such amount shall not be paid in such year. Such nondeductible amount
shall be payable in the following calendar year, as an addition to the annual
installment scheduled to be paid in such following calendar year, if applicable,
subject to the provisions of this Section 7.8.

ARTICLE 8--PLAN ADMINISTRATOR

8.1 PLAN ADMINISTRATION AND INTERPRETATION

    The Plan Administrator shall oversee the administration of the Plan. The
Plan Administrator shall have complete control and authority to determine the
rights and benefits and all claims, demands and actions arising out of the
provisions of the Plan of any Participant, beneficiary, deceased Participant, or
other person having or claiming to have any interest under the Plan. The Plan
Administrator shall have complete discretion to interpret the Plan and to decide
all matters under the Plan. Such interpretation and decision shall be final,
conclusive and binding on all Participants and any person claiming under or
through any Participant, in the absence of clear and convincing evidence that
the Plan Administrator acted arbitrarily and capriciously. Any individual(s)
serving as Plan Administrator who is a Participant will not vote or act on any
matter relating solely to himself or herself. In such case, General Instrument
Corporation will appoint an individual to act as Plan Administrator to take such
actions. When making a determination or calculation, the Plan Administrator
shall be entitled to rely on information furnished by a Participant, a
beneficiary, the Company or the Trustee. The Plan Administrator shall have the
responsibility for complying with any reporting and disclosure requirements of
ERISA.

8.2 POWERS, DUTIES, PROCEDURES, ETC.

    The Plan Administrator shall have such powers and duties, may adopt such
rules and tables, may act in accordance with such procedures, may appoint such
officers or agents, may delegate such powers and duties, may receive such
reimbursements, and shall follow such claims and appeal procedures with respect
to the Plan as it may establish.

8.3 INFORMATION

    To enable the Plan Administrator to perform its functions, the Company shall
supply full and timely information to the Plan Administrator on all matters
relating to the compensation of Participants, their employment, retirement,
death, termination of employment, and such other pertinent facts as the Plan
Administrator may require.

8.4 INDEMNIFICATION OF PLAN ADMINISTRATOR

    The Company agrees to indemnify and to defend to the fullest extent
permitted by law any officer(s) or employee(s) who serve as Plan Administrator
(including any such individual, whether a present or former employee, who
formerly served as Plan Administrator) against all liabilities, damages, costs
and expenses (including attorneys' fees and amounts paid in settlement of any
claims approved by General Instrument Corporation) occasioned by any act or
omission to act in connection with the Plan, if such act or omission is in good
faith.

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ARTICLE 9--AMENDMENT AND TERMINATION

9.1 AMENDMENTS

    General Instrument Corporation shall have the right to amend the Plan from
time to time, subject to Section 9.3, by an instrument in writing which has been
executed on its behalf by its Chief Executive Officer or his delegate designated
in writing, with or without the specific approval of the board of directors.

9.2 TERMINATION OF PLAN

    This Plan is strictly a voluntary undertaking on the part of the Company and
shall not be deemed to constitute a contract between the Company and any
Eligible Employee (or any other employee) or a consideration for, or an
inducement or condition of employment for, the performance of the services by an
Eligible Employee (or other employee). General Instrument Corporation reserves
the right to terminate the Plan at any time, subject to Section 9.3, by an
instrument in writing which has been executed on its behalf by its Chief
Executive Officer or his delegate designated in writing, with or without the
specific approval of the board of directors. In addition, the Plan shall
terminate upon a Change of Control in accordance with Section 7.2. Upon
termination other than pursuant to Section 7.2, General Instrument Corporation
may (a) elect to continue to maintain the Trust to pay benefits hereunder as
they become due as if the Plan had not terminated or (b) amend the Trust as
provided therein to require prompt payment to Participant's (or their
beneficiaries) of the balance of their Accounts.

9.3 EXISTING RIGHTS

    No amendment or termination of the Plan shall adversely affect the rights of
any Participant with respect to amounts that have been credited to his or her
Account prior to the date of such amendment or termination.

ARTICLE 10--MISCELLANEOUS

10.1 NO FUNDING

    The Plan constitutes a mere promise by the Company to make payments in
accordance with the terms of the Plan and Participants and beneficiaries shall
have the status of general unsecured creditors of the Company. Nothing in the
Plan will be construed to give any employee or any other person rights to any
specific assets of the Company or of any other person. In all events, it is the
intent of the Company that the Plan be treated as unfunded for tax purposes and
for purposes of Title I of ERISA.

10.2 NON-ASSIGNABILITY

    None of the benefits, payments, proceeds or claims of any participant or
beneficiary shall be subject to any claim of any creditor of any Participant or
beneficiary, nor shall any Participant or beneficiary have any right to
alienate, anticipate, commute, pledge, encumber or assign any of the benefits or
payments or proceeds which he or she may expect to receive, contingently or
otherwise, under the Plan.

10.3 LIMITATION OF PARTICIPANT'S RIGHTS

    Nothing contained in the Plan shall confer upon any person a right to be
employed or to continue in the employ of the Company, or interfere in any way
with the right of the Company to terminate the employment of a Participant in
the Plan at any time, with or without cause.

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10.4 PARTICIPANTS BOUND

    Any action with respect to the Plan taken by General Instrument Corporation,
the Plan Administrator or the Company or the Trustee or any action authorized by
or taken at the direction of the General Instrument Corporation, the Plan
Administrator, the Company or the Trustee shall be conclusive upon all
Participants and beneficiaries entitled to benefits under the Plan.

10.5 RECEIPT AND RELEASE

    Any payment to any Participant or beneficiary in accordance with the
provisions of the Plan shall, to the extent thereof, be in satisfaction of
claims against the Company, the Plan Administrator and the Trustee under the
Plan, and the Plan Administrator may require such Participant or beneficiary, as
a condition precedent to such payment, to execute a receipt and release to such
effect. If any Participant or beneficiary is determined by the Plan
Administrator to be incompetent by reason of physical or mental disability,
including minority, to give a valid receipt and release, the Plan Administrator
may cause the payment or payments becoming due to such person to be made to
another person for his or her benefit without responsibility on the part of the
Plan Administrator, the Company or the Trustee to follow the application of such
funds.

10.6 GOVERNING LAW

    The Plan shall be construed, administered, and governed in all respects
under and by the laws of the State of Pennsylvania. If any provision shall be
held by a court of competent jurisdiction to be invalid or unenforceable, the
remaining provisions hereof shall continue to be fully effective.

10.7 HEADINGS AND SUBHEADINGS

    Headings and subheadings in this Plan are inserted for convenience only and
are not to be considered in the construction of the provisions hereof.
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<S>                                          <C>        <C>                                        <C>
Dated: 2 March, 1998                         GENERAL INSTRUMENT CORPORATION

                                                               By:

<CAPTION>
                                                               /s/ SCOTT CRUM

                                                               ------------------------------------------

                                                               Name: Scott Crum

                                                               Title:  VICE PRESIDENT, ADMINISTRATION

                                                                     AND EMPLOYEE RESOURCES

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