Exhibit 10.5

[*] Certain information in this document has been omitted and filed separately
with the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

LOGO [g236739g09o81.jpg]

Codexis, Inc.

200 Penobscot Drive

Redwood City, CA 94063

Tel: 650.421.8100

Fax: 650.421.8102

www.codexis.com

August 17, 2011

Arch Pharmalabs Limited

Attn: Company Secretary

H wing, 4th Floor

Tex Centre

Off Saki Vihar Road

Chandivali, Mumbai- 400072

India

Codexis India, Inc.

G-01, Prestige Loka,

7/1 Brunton Road

Bangalore – 560 025

India

 

RE: The Enzyme and Product Supply Agreement between Arch Pharmalabs Limited
(“Arch”) and Codexis, Inc. (“Codexis”), effective as of February 16, 2010 (the
“EPSA”), and the Product Supply Agreement between Arch and Codexis Laboratories
India Private Limited (“Codexis India”), effective as of February 16, 2010 (the
“PSA”)

Dear Sirs:

This letter serves to confirm that Codexis, Codexis India and Arch mutually
desire to amend the EPSA and PSA in the following manner in order to permit Arch
to sell to [*] (as defined in the EPSA and PSA):

 

  1. Section 1.16 of the EPSA shall be amended in its entirety and replaced with
the following:

1.16 “Codexis Customers” shall mean (i) Third Party Innovator Companies located
throughout the world (other than in India); and (ii) Third Party Generic
Companies located in the United States, Canada, and Israel (except[*]), and
their

 

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[*] Certain information in this document has been omitted and filed separately
with the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

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respective commonwealths, territories and possessions, and Europe.
Notwithstanding anything to the contrary in this Agreement, [*] are not a
Codexis Customer.

 

  2. Section 1.21 of the EPSA shall be amended in its entirety and replaced with
the following:

1.21 “Codexis India Customers” shall mean (i) Third Party Innovator Companies in
India; and (ii) the following companies in India: [*], as the foregoing list may
be updated or modified pursuant to written agreement of the Parties.

 

  3. Section 1.10 of the PSA shall be amended in its entirety and replaced with
the following:

1.10 “Codexis India Customers” shall mean (i) Third Party Innovator Companies in
India; and (ii) the following companies in India: [*], as the foregoing list may
be updated or modified pursuant to written agreement of the Parties.

All provisions of the EPSA and PSA not expressly amended by this letter shall
remain in full force and effect. Please indicate your agreement to the above by
countersigning each enclosed triplicate of this letter and returning one
original to me.

We look forward to the continued success of our relationship.

Very truly yours,

 

Codexis, Inc. By:   /s/    Joseph Sarrett   Name: Joseph Sarret   Title: Chief
Business Officer

 

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[*] Certain information in this document has been omitted and filed separately
with the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

LOGO [g236739g09o81.jpg]

 

Acknowledged, agreed and accepted by: Codexis Laboratories India Private Limited
By:   /s/    Alan Shaw   Name: Alan Shaw   Title: Director Date:   August 18,
2011

Acknowledged, agreed and accepted by: Arch Pharmalabs Limited By:   /s/    Ajit
Kamath   Name: Ajit Kamath   Title: Chairman & Managing Director Date:  
August 20, 2011

Copies to:

Arch Pharmalabs Limited

H wing, 4th Floor

Tex Centre

Off Saki Vihar Road

Chandivali, Mumbai- 400072

India

Attn: Chairman and Managing Director

Facsimile: +912228471234

 

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