Exhibit 10.42

ADDENDUM INCORPORATING

EGTRRA COMPLIANCE AMENDMENT

TO

TELLABS 401(K) PLAN (THE
PLAN)

This Amendment to the Plan is adopted to reflect certain provisions of the Economic Growth and Tax Relief Reconciliation Act of 2001
(EGTRRA). This Amendment is intended as good faith compliance with the requirements of EGTRRA and is to be construed in accordance with EGTRRA and guidance issued thereunder. Except as otherwise provided, this Amendment shall be
effective as of the first day of the first Plan Year beginning after December 31, 2001.

This Amendment shall supersede the provisions of the Plan to
the extent those provisions are inconsistent with the provisions of this Amendment.

References to provisions by Plan Section or Article numbers in this
Amendment are to the provisions associated with these Section or Article numbers in the approved volume submitter specimen plan from which the Plan is generated. If the Section or Article numbers have been changed in generating the Plan, references
are to the provisions in the Plan that are associated with the Section or Article numbers in the approved volume submitter specimen plan.

AMENDMENT
SECTION 1: PLAN LOANS FOR OWNER-EMPLOYEES AND SHAREHOLDER EMPLOYEES



|[X] | Select this Amendment Section 1 if the Plan provides for loans. (Do not select if the Plan does not provide for loans.)
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Effective for plan loans made after December 31, 2001, the provisions of Section 12.1 prohibiting loans to any owner-employee or
shareholder-employee shall cease to apply.

AMENDMENT SECTION 2: LIMITATIONS ON CONTRIBUTIONS



|[X] | All Plans must select this Amendment Section 2.
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Effective for limitation years beginning after December 31, 2001, the first sentence of the Section in Article VII entitled Code Section 415 Limitations on Crediting of Contributions and Forfeitures is
amended to provide as follows:

Except to the extent permitted under Amendment Section 11 and Code Section 414(v), if applicable,
the annual addition that may be contributed or allocated to a Participants Account under the Plan for any limitation year shall not exceed the lesser of:



| | (a) | $40,000, as adjusted for increases in the cost-of-living under Code Section 415(d), or
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| | (b) | 100 percent of the Participants compensation, within the meaning of Code Section 415(c)(3), for the limitation year. The compensation limit referred to in
this paragraph (b) shall not apply to any contribution for medical benefits after separation from service (within the meaning of Code Section 401(h) or 419A(f)(2)) which is otherwise treated as an annual addition.
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AMENDMENT SECTION 3: INCREASE IN COMPENSATION LIMIT



|[X] | Select this Amendment Section 3 to increase the Compensation limit applicable under Code Section 401(a)(17) to the new $200,000 limit. (If you do not wish to
increase to the new Compensation limit, do not select this Amendment Section 3.)
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The annual Compensation of each
Participant taken into account in determining allocations for any Plan Year beginning after December 31, 2001, shall not exceed $200,000, as adjusted for cost-of-living increases in accordance with Code Section 401(a)(17)(B). Annual
Compensation means Compensation during the Plan Year or such other consecutive 12-month period over which Compensation is otherwise determined under the Plan (the determination period). The cost-of-living adjustment in effect for a calendar year
applies to annual Compensation for the determination period that begins with or within such calendar year.

AMENDMENT SECTION 4: MODIFICATION OF TOP-HEAVY
RULES



|[X] | Select this Amendment Section 4 if the Plan covers non-collectively bargained employees. (If the Plan covers collectively bargained employees only, do not
select this Amendment Section 4.)
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This Section shall apply for purposes of determining whether the Plan is a
top-heavy plan under Code Section 416(g) for Plan Years beginning after December 31, 2001, and whether the Plan satisfies the minimum benefits requirements of Code Section 416(c) for such years. This Section amends Article XXII of the
Plan



| | A. | The definition of key employee in Section 22.1 is amended to provide as follows:
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A key employee means any Employee or former Employee (including any deceased Employee) who at any time during the Plan Year that
includes the determination date was an officer of an Employer or a Related Company having annual compensation greater than $130,000 (as adjusted under Code Section 416(i)(1) for Plan Years beginning after December 31, 2002), a
5-percent owner of an Employer or a Related Company, or a 1-percent owner of an Employer or a Related Company having annual compensation of more than $150,000.



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For this purpose, annual compensation means compensation within the meaning of Code Section 415(c)(3). The determination of who is a key
employee will be made in accordance with Code Section 416(i)(1) and the applicable regulations and other guidance of general applicability issued thereunder.



| | B. | The definition of top heavy plan in Section 22.1 is modified for purposes of determining the present values of accrued benefits and the amounts of account balances
of employees as of a determination date as follows:
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The present values of accrued benefits and the amounts of
account balances of an Employee as of the determination date shall be increased by the distributions made with respect to the Employee under the Plan and any plan aggregated with the Plan under Code Section 416(g)(2) during the
one-year period ending on the determination date. The preceding sentence shall also apply to distributions under a terminated plan which, had it not been terminated, would have been aggregated with the Plan under Code
Section 416(g)(2)(A)(i). In the case of a distribution made for a reason other than separation from service, death, or disability, this provision shall be applied by substituting five-year period for one-year period. The
accrued benefits and accounts of any individual who has not performed services for an Employer or any Related Company during the one-year period ending on the determination date shall not be taken into account.



| | C. | The Section in Article XXII entitled Minimum Employer Contributions is modified in the following respect:
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Employer matching contributions shall be taken into account for purposes of satisfying the minimum contribution requirements of Code
Section 416(c)(2) of the Plan. The preceding sentence shall apply with respect to Matching Contributions under the Plan or, if the Plan provides that the minimum contribution requirement shall be met in another plan, such other plan. Employer
matching contributions that are used to satisfy the minimum contribution requirements shall be treated as matching contributions for purposes of the actual contribution percentage test and other requirements of Code Section 401(m).



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AMENDMENT SECTION 5: DIRECT ROLLOVERS OF PLAN DISTRIBUTIONS



|[X] | All Plans must select this Amendment Section 5.
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Effective with respect to distribution made after December 31, 2001, the Section in Article XVI entitled Direct Rollovers is amended in the following respects:



| | A. | The definition of eligible retirement plan in paragraph (a) is modified by the addition of a new sentence at the end thereof to provide as follows:
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An eligible retirement plan shall also mean an annuity contract described in Code Section 403(b) and an
eligible plan under Code Section 457(b) which is maintained by a state, political subdivision of a state, or any agency or instrumentality of a state or political subdivision of a state and which agrees to separately account for amounts
transferred into such plan from this plan. The definition of eligible retirement plan shall also apply in the case of a distribution to a surviving spouse, or to a spouse or former spouse who is the alternate payee under a qualified
domestic relation order, as defined in Code Section 414(p).



| | B. | If the Plan provides for hardship withdrawals, the definition of eligible rollover distribution in paragraph (b) is modified to exclude ALL hardship distributions.
Any amount that is distributed on account of hardship shall not be an eligible rollover distribution and the distributee may not elect to have any portion of such a distribution paid directly to an eligible retirement plan.
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| | C. | If the Plan includes assets attributable to After-Tax Contributions, the definition of eligible rollover distribution in paragraph (b) is modified to eliminate the
exclusion of After-Tax Contributions. A portion of a distribution shall not fail to be an eligible rollover distribution merely because the portion consists of After-Tax Contributions that are not includible in gross income. However,
such portion may be transferred only to an individual retirement account or annuity described in Code Section 408(a) or (b), or to a qualified defined contribution plan described in Code Section 401(a) or 403(a) that agrees to separately
account for amounts so transferred, including separately accounting for the portion of such distribution which is includible in gross income and the portion of such distribution which is not so includible.
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AMENDMENT SECTION 6: ROLLOVERS FROM OTHER PLANS



|[X] | Select this Amendment Section 6 and complete the selections below only if the Plan accepts Rollover Contributions.
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Effective with respect to distributions made after December 31, 2001, the Section of Article V entitled Rollover Contributions is amended
to provide the following:



| | A. | The Plan will accept as a Rollover Contribution a direct rollover (the rollover is made directly from the other qualified plan or annuity contract) of an
eligible rollover distribution from (select all that apply):
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| | [X] | a qualified plan described in Code Section 401(a) or 403(a), excluding after-tax employee contributions.
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| | [   ] | a qualified plan described in Code Section 401(a) or 403(a), including after-tax employee contributions. (Do not select if the preceding selection is marked.)
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| | [X] | an annuity contract described in Code Section 403(b), excluding after-tax employee contributions.
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| | [X] | an eligible plan under Code Section 457(b) which is maintained by a state, political subdivision of a state, or any agency or instrumentality of a state or political
subdivision of a state.
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| | [   ] | none of the above.
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| | B. | The Plan will accept as a Rollover Contribution a participant rollover (the rollover amount is first distributed to the participant who then rolls it over into the
Plan) of an eligible rollover distribution from (select all that apply):
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| | [X] | a qualified plan described in Code Section 401(a) or 403(a).
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| | [X] | an annuity contract described in Code Section 403(b).
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| | [X] | an eligible plan under Code Section 457(b) which is maintained by a state, political subdivision of a state, or any agency or instrumentality of a state or political
subdivision of a state.
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| | [   ] | none of the above.
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| | C. | Select one of the following:
| | -- | ----------------------------



| | [   ] | The Plan will accept as a Rollover Contribution a direct or participant rollover of the portion of a distribution from an individual retirement account or annuity described
in Code Section 408(a) or 408(b) that is eligible to be rolled over and would otherwise be includible in gross income.
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or



| | [X] | The Plan will not accept as a Rollover Contribution a direct or participant rollover of the portion of a distribution from an individual retirement account or annuity
described in Code Section 408(a) or 408(b) that is eligible to be rolled over and would otherwise be includible in gross income.
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AMENDMENT SECTION 7: ROLLOVERS DISREGARDED IN INVOLUNTARY CASH-OUTS



|[   ] | This Amendment Section 7 may be selected if the Plan provides for involuntary cash-outs. If this Amendment Section 7 is selected complete the fill-ins below. Note
that this Amendment will result in the involuntary distribution of a separated Participants Account over $5,000 if the portion of the Account that is not attributable to Rollover Contributions is $5,000 or less.
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For purposes of the Section in Article XV entitled Cash Outs and Participant Consent, the value of a
Participants vested interest in his Account shall be determined without regard to that portion of the account balance that is attributable to Rollover Contributions (and earnings allocable thereto) within the meaning of Code Sections 402(c),
403(a)(4), 403(b)(8), 408(d)(3)(A)(ii), and 457(e)(16). If the value of the Participants vested interest in his Account as so determined is $5,000 or less, the Plan shall immediately distribute the Participants entire vested interest in
his Account.

AMENDMENT SECTION 8: REPEAL OF MULTIPLE USE TEST

If applicable, the Section of Article VII entitled Multiple Use Limitation shall not apply for Plan Years beginning after December 31, 2001.

AMENDMENT SECTION 9. MODIFICATION OF TOP-HEAVY RULES FOR SAFE HARBOR PLANS



|[X] | Select this Amendment Section 9 if the Plan consists solely of a cash or deferred arrangement which is intended to meet the safe harbor requirements of Code
Section 401(k)(12) and Matching Contributions with respect to which the safe harbor requirements of Code Section 401(m)(11) are intended to be met.
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The top-heavy requirements of Code Section 416 and Article XXII of the Plan shall not apply in any year beginning after December 31, 2001, in
which the Plan consists solely of a cash or deferred arrangement which meets the requirements of Code Section 401(k)(12) and Matching Contributions with respect to which the requirements of Code Section 401(m)(11) are met.

AMENDMENT SECTION 10: CATCH-UP CONTRIBUTIONS



|[X] | Select this Amendment Section 10 and complete the fill-in below only if the Plan provides for Tax-Deferred Contributions.
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All Eligible Employees who have attained age 50 before the close of the Plan Year shall be eligible to make catch-up contributions in
accordance with, and subject to the limitations of, Code Section 414(v). Such catch-up contributions shall



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not be taken into account for purposes of the provisions of the Plan implementing the required limitations of Code Sections 402(g) and 415. The Plan shall
not be treated as failing to satisfy the provisions of the Plan implementing the requirements of Code Section 401(k)(3), 401(k)(11), 401(k)(12), 410(b), or 416, as applicable, by reason of the making of such catch-up contributions.



| | [   ] | Tax-Deferred Contributions that are treated as catch-up contributions are excluded from eligibility for Matching Contributions under the Plan.
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AMENDMENT SECTION 11: SUSPENSION PERIOD FOLLOWING HARDSHIP DISTRIBUTION



|[X] | Selection of this Amendment Section 11 is optional for 401(k) plans, other than plans described in Code Section 401(k)(12) or 401(m)(11) (i.e., plans that provide
for safe harbor contributions to satisfy the discrimination testing rules), that use the safe harbor (deemed) standards for hardship withdrawals of Tax-Deferred Contributions set forth in Treas. Reg. Section 1.401(k)-1(d)(2)(iv). This Amendment
Section 11 is required for a plan described in Code Section 401(k)(12) or 401(m)(11) (i.e., plans that provide for safe harbor contributions to satisfy the discrimination testing rules) and that provide for hardship withdrawals. Also see
Notice 2001-56 for guidance regarding the effective date of the change made by EGTRRA Section 636(a).
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If
you select this Amendment Section 11 the automatic suspension of elective contributions following a hardship withdrawal will be reduced from 12 months to 6 months.

A Participant who makes a hardship withdrawal of Tax-Deferred Contributions on or after the effective date specified below, shall be prohibited from
making elective contributions and employee contributions, as defined in Section 7.1, under the Plan and all other plans maintained by an Employer or a Related Company for six months after receipt of the withdrawal.

This provision is effective January 1, 2004.

AMENDMENT SECTION 12: ELIMINATION OF REDUCTION IN 402(g) LIMIT FOR YEAR FOLLOWING YEAR IN WHICH HARDSHIP DISTRIBUTION MADE



|[X] | Selection of this Amendment Section 12 is optional for 401(k) plans, other than plans described in Code Section 401(k)(12) or 401(m)(11) (i.e., plans that provide
for safe harbor contributions to satisfy the discrimination testing rules), that use the safe harbor (deemed) standards for hardship withdrawals of Tax-Deferred Contributions set forth in Treas. Reg. Section 1.401(k)-1(d)(2)(iv). This Amendment
Section 12 is required for a plan described in Code Section 401(k)(12) or 401(m)(11) (i.e., plans that provide for safe harbor contributions to satisfy the discrimination testing rules) and that provide for hardship withdrawals. Also, see
Notice 2001-56 for guidance regarding the effective date of the change made by EGTRRA Section 636(a).
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If you select this Amendment Section 12 the reduction in the maximum Tax-Deferred
Contributions that a participant may make under Code Section 402(g) in the year following a hardship distribution for contributions made in the year of the distribution will be eliminated.

A Participant who makes a hardship withdrawal of Tax-Deferred Contributions on or after the effective date specified below, shall not have his maximum
Tax-Deferred Contributions and elective contributions for the taxable year following the taxable year of the withdrawal reduced under Code Section 402(g) by the amount of his Tax-Deferred Contributions and elective
contributions for the taxable year of the withdrawal.

This provision is effective January 1, 2004.

AMENDMENT SECTION 13: DISTRIBUTION UPON SEVERANCE FROM EMPLOYMENT



|[X] | This Amendment Section 13 should be selected and the selections and fill-ins below completed if your Plan provides for tax-deferred contributions and you want deferrals
and related costs to be distributable in the event you sell off assets and want employees who continue employment with the buyer to be paid out of the Plan.
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A Participants Tax-Deferred Contributions Sub-Account, Qualified Nonelective Contributions Sub-Account, and Qualified Matching Contributions
Sub-Account shall be distributed on account of the Participants severance from employment. However, such a distribution shall be subject to the other provisions of the Plan regarding distributions, other than provisions that require a
separation from service before such amounts may be distributed.

*            *            *

EXECUTED AT TELLABS, this 29th day of August, 2007.



By:

/s/ Kyle MatthewsTitle:

VP, Human Resources




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