SUPPLEMENTAL AGREEMENT TO JOINT VENTURE AGREEMENT DATED DECEMBER 19, 1997

1.

CHARTERED SEMICONDUCTOR MANUFACTURING LTD (“ CSM ”), a company incorporated under the laws of Singapore and having its registered address at 60 Woodlands Industrial Park D Street 2 Singapore 738406 on the one part; and

2.

AGERE SYSTEMS SINGAPORE PTE LTD (“ AGERE ”), a company incorporated under the laws of Singapore and having its registered address at 3 Kallang Sector, Kolam Ayer Industrial Park, Singapore 349278 on the other part.

A.

A Joint Venture Agreement relating to the incorporation and management of SILICON MANUFACTURING PARTNERS PTE LTD (“ SMP ”) was entered into between CSM and LUCENT TECHNOLOGIES MICROELECTRONICS PTE LTD (“ Lucent ”) on 19 December 1997, and subsequently assigned by Lucent to AGERE (the “ JVA ”) on 1 February 2001.

B.

AGERE and CSM further entered into the SMP Cash Distribution Agreement on 5 March 2004 (“ Cash Distribution Agreement ”) to address the cash investment imbalances between AGERE and CSM in SMP, and to achieve a cash investment in SMP in the proportion of the equity shareholdings of AGERE and CSM in SMP.

C.

As contemplated under the Cash Distribution Agreement, AGERE and CSM now desire to make amendments to the JVA and Articles of Association of SMP on the terms and subject to the conditions set out hereunder.

1.

AMENDMENTS TO THE JVA

The parties agree that the following Clauses under the JVA shall be amended as follows:

1.1

Clause 1

1.1.1

Clause 1 shall be amended by inserting the following word and its corresponding definition after the word “Affiliate” and its corresponding definition:-

“Agere” means Agere Systems Singapore Pte Ltd, a company incorporated in Singapore with its registered address at 3 Kallang Sector, Kolam Ayer Industrial Park, Singapore 349278;”

In connection thereto, the parties agree that all references to the word “Lucent” in the JVA, other than in Recital A, the definitions of “Completion”, “Lucent Fiscal Month”, “Lucent Fiscal Quarter”, “Lucent Fiscal Year”, Clauses 3(E), 4, 6, 7(A)(vi), 7A(vii), 7A(viii), 7(B), 10(C), 10(E)(ii), 14(A), 14(F), 19(A), 19(F), 19(L) and Schedule A, shall be deleted and substituted with the word “Agere”.

1.1.2

Under the definition of “Indebtedness”, sub-clause (iv) shall be amended by deleting it in its entirety and substituting it with the following:-

“(iv)

all obligations of such Person as lessee under leases that have been or should be, in accordance with Singapore GAAP, U.S. GAAP or any other accounting principles as approved by the Board, recorded as capital leases;”

1.1.3

Under the definition of “Net Book Value”, the first paragraph shall be amended by deleting it in its entirety and substituting it with the following:-

“means the net worth (assets less liabilities) of the Company as of the most recently audited balance sheet date as updated to the Net Book Value Request Date or the Termination Date, as applicable. The net worth of the Company is derived by adding the original cost value of the Company’s assets less normal charges for depreciation and other adjustments as prescribed by Singapore GAAP, U.S. GAAP or any other accounting principles as approved by the Board, and subtracting the liabilities of the Company.”

1.2

Clause 7(A)

1.2.1

Clause 7(A)(v) shall be amended by deleting it in its entirety and substituting it with the following:

“(v)

for each financial year, the Company shall, at its expense, prepare annual accounts, in each case in accordance with Singapore GAAP, U.S. GAAP or any other accounting principles as approved by the Board, and in compliance with all applicable legislation in respect of such financial year and shall procure that such accounts are audited as soon as practicable and shall supply copies of the same, both in draft and final form, to each of the Shareholders within 90 days (in the case of the draft form) and 120 days (in the case of the final form) after the end of the financial year of the Company;”

1.2.2

Clause 7(A)(vi) shall be amended by deleting it in its entirety and substituting it with the following:

“(vi)

the Company shall, at its expense, (a) prepare interim accounts of the Company covering the period beginning on January 1 and ending on September 30 of each calendar year, (b) procure that such interim accounts are audited within 60 days after the end of the Agere Fiscal Year in accordance with Singapore GAAP, U.S. GAAP or any other accounting principles as approved by the Board, and in compliance with all applicable legislation in respect of such interim period and (c) supply copies of such audited interim accounts in final form to Agere within 60 days after the end of the Agere Fiscal Year;”

1.2.3

Clause 7(A)(viii) shall be amended by including the words “,U.S. GAAP or any other accounting principles as approved by the Board” after the words “in each case in accordance with Singapore GAAP” in the last line.

1.3

Clause 12

Clause 12 shall be amended by deleting it in its entirety and substituting it with the following:

“ 12.

DIVIDEND POLICY

The dividends of the Company shall be recommended by the Board from time to time, and to the extent permitted by law, determined on a year to year basis and not on a cumulative basis. The Company shall procure that in making any recommendation therefor, the Board shall endeavour to distribute by way of dividends as soon as permissible under applicable laws, the maximum allowable amount of its profits available for distribution after taking into account the working capital requirement and growth plans of the Company and other provisions and reserves as may be required by law. It is not the intention of the Shareholders for the Company to accumulate excess retained earnings beyond what is reasonably required for the needs of the Company. Accordingly, and in furtherance of the foregoing, each Shareholder shall take such action as may be necessary to procure that the Company shall distribute all available cash to and among the Shareholders during such times and in such amounts as contemplated by this Agreement and in the Articles.”

2.

AMENDMENT TO THE ARTICLES OF ASSOCIATION

2.1

The parties hereto agree that the Articles of SMP shall be amended in accordance with Clause 5(I)(g) of the JVA, in substantially the same form as set out in Annex 1, to ensure that the provisions in the Articles are consistent with the terms and conditions of the JVA as supplemented by this Supplemental Agreement.

2.2

For the purposes of Clauses 2.3 and 2.4:

2.2.1

“ Cumulative Profit ” or “ Cumulative Loss ” means the aggregate of all Quarterly A Profits and Quarterly A Losses or Quarterly B Profits and Quarterly B Losses (as the case may be) less any Interim Dividends declared to the party with respect to such Profits at any time during any Financial Year;

2.2.2

“ Financial Year ” means any financial year of SMP, commencing from the financial year beginning on 1 January 2004;

2.2.3

“ Quarterly A Loss ” means, with respect to each quarter of any Financial Year, the negative figure that results from the application of the formula contained in Article 119A(4) of the Articles of SMP save that any reference to “financial year” in the definitions of “AGS”, “ATMC”, “AO” and “ATAX” shall be replaced with “quarter of that Financial Year”;

2.2.4

“ Quarterly A Profit ” means, with respect to each quarter of any Financial Year, the positive figure that results from the application of the formula contained in Article 119A(4) of the Articles of SMP save that any reference to “financial year” in the definitions of “AGS”, “ATMC”, “AO” and “ATAX” shall be replaced with “quarter of that Financial Year”;

2.2.5

“ Quarterly B Loss ” means, with respect to each quarter of any Financial Year, the negative figure that results from the application of the formula contained in Article 119A(5) of the Articles of SMP save that any reference to “financial year” in the definitions of “BGS”, “BTMC”, “BO” and “BTAX” shall be replaced with “quarter of that Financial Year”;

2.2.6

“ Quarterly B Profit ” means, with respect to each quarter of any Financial Year, the positive figure that results from the application of the formula contained in Article 119A(5) of the Articles of SMP save that any reference to “financial year” in the definitions of “BGS”, “BTMC”, “BO” and “BTAX” shall be replaced with “quarter of that Financial Year”;

2.2.7

“ Quarterly Loss ” means, with respect to each quarter of any Financial Year, the Quarterly A Loss or the Quarterly B Loss; and

2.2.8

“ Quarterly Profit ” means, with respect to each quarter of any Financial Year, the Quarterly A Profit or the Quarterly B Profit.

2.3

To the extent permitted by law and without prejudice to the generality of Clause 12 of the JVA:

2.3.1

in the event that there is a Quarterly A Profit or a Quarterly B Profit (as the case may be) in respect of any quarter of a Financial Year, the parties hereto agree that if so requested by the party entitled to such Quarterly Profit (the “ Entitled Party ”) (it being understood that CSM is entitled to the Quarterly A Profit and AGERE is entitled to the Quarterly B Profit), the Company shall declare and distribute to the Entitled Party as interim dividends (the “ Interim Dividend ”):

(i)

the full amount of the Quarterly Profit (or such lower amount as the Entitled Party may elect) and, subject to the other provisions hereof, each party agrees to take such action as may be necessary to procure and ensure that the Directors appointed by such party shall vote in favour of a board resolution declaring and distributing such Interim Dividen