SecProbe.io

November 16, 2012

Via E -mail
Mr. David R. Demers
Chief Executive Officer
Westport Innovations Inc.
Suite 101, 1750 West 75th Avenue
Vancouver, British Columbia, Canada  V6P 6G2

 Re: Westport Innovations Inc.
  Amendment No. 2 to Form 40-F for the Nine Months
  Ended  December 31, 201 1
Filed October 29, 2012
  File No.  1-34152

Dear Mr.  Demers :

We have reviewed your response letter  dated October 29, 2012  and have the following
comments.   In some of our comments, we may ask you to provide us with information so we
may better understand your disclosure.

Please respond to this letter within ten business days by providing the requested
information  or by advising us when you will provide the requested response.  If you do not
believe our comments a pply to your facts and circumstances, please tell us why in your response.

After reviewing the information you provide in response to these comments, we may
have  additional comments.

Amendment No. 2 to Form 40 -F for the Nine Months Ended December 31, 2 011

Exhibit 99.2

Note 21. Investment in Joint Ventures, page 37

(a) Cummins Westport Inc., page 37

1. Further to your responses to prior comments 1 and 2, i n determining whether or not CWI
is a VIE, we note that you point to the fact that Westport  guarant eed the losses of CWI
during the 2004 calendar year and received the entire benefit of any financial profits of
CWI up to and including December 31, 2004.  We note that after December 31, 2004,
Westport and Cummins share equally in the profits and losses o f CWI.  Please discuss
how you considered the temporary nature of Westport’s obligations during 2004, whether

Mr. David R. Demers
Westport Innovations Inc.
November 16, 2012
Page 2

 these terms were substantive and how you considered t hat under FASB ASC  810-10-25-
37, the determination of whether a legal entity is a VIE should be based on the
circumstances on that date including future changes that are required in existing
governing documents and existing contractual arrangements.
2. We note the following from your responses to prior comments 1 and 2 and the disclosure
in your Form  40-F:

 Cummins and Westport each own 50% of the common shares of CWI.  No
preferred shares have been issued. There are no differences in the rights or
responsibilities attached to Cummins’ common shares as compared to Westport’s
common shares .
 From January  1, 2005, Cummins and Westport share equally in the profits and
losses of CWI.
 Westport and Cummins have equal representation on the Board of Directors.
 CWI is primarily responsible to obtain the financing resources it requires for any
and all working capital, capital expenditures, and financial requirements.  While
CWI may request financing from the holders of the common shares , Wes tport and
Cummins  have no obligation to provide such financial resources or to assist CWI
in terms of third party guaranties or otherwise.

Given the above, please tell us in more detail how you determined that Westport (a) has
the power to direct the activities of CWI  that most significantly impact CWI ’s economic
performance  and (b) t he obligation to absorb losses of  CWI  that could potentially be
significant to CWI  or the right to receive benefits from CWI that could potentially be
significant to CWI .  Refer to FASB ASC 810 -10-25-38A and 38B.

3. Your response notes that while Westport and Cummins have equal representat ion on the
Board of Directors, CWI makes up the majority of Westport’s revenue and profitability
while it is a much less significant part of Cummins global business.   As such, Westport’s
executive team is actively involved in CWI’s business plan and strate gy while Cummins
plays less of an active role.

 Please describe to us in detail the actions of the Westport executive team in CWI’s
business plan and strategy.
 Discuss how you considered that under FASB ASC 810 -10-25-38B, a reporting entity
does not have  to exercise its power in order to have power to direct the activities of a
VIE.

4. Describe to us the specific actions being undertaken by the Westport executive team that
demonstrate s that they are actively involved in CWI.  Explain whether Cummins has t he
right to perform similar tasks but has chosen not to exercise that right.  Please bridge the
gap for us between these “actively involved” actions undertaken by Westport’s executive

Mr. David R. Demers
Westport Innovations Inc.
November 16, 2012
Page 3

 team and your conclusion that Westport has the power  to direct the activities of CWI that
most significantly impa ct CWI’s economic performance.

5. You told us that Westport is also responsible for the management of the CWI treasury
function and makes decisions on reinvestment of excess cash balances.   Pleas e tell us
more about the scope of these activities and the extent to which you exercise unilateral
control.

6. Further, we note from your response that Cummins has the power to direct CWI’s
manufacturing and distribution activities.  Explain further why thes e activities are not
considered those that most significantly impact CWI’s economic performance.  In this
regard, please further address FASB ASC 810 -10-25-38D and 38E and whether or not
power is shared between Westport and Cummins.  Refer to Case H1 of Ex ample 5 in
FASB ASC 810 -10-55-184 through 55 -192.

7. You told us that t he Second Amended and Restated JVA includes terms whereby
Westport and Cummins may become  entitled to receive a Performance Bonus  of which
75% is distributed to  Westport  and 25% in distributed to  Cummins .  Please tell us in
more detail about the Performance Bonus, including whether this is a substantive term of
the agreement (and why or why not) and how the parties determined the appropriate
distribution percentages.  Refer to FASB A SC 810 -10-25-38G.

8. We note from your response in Exhibit B that certain decisions cannot be acted upon
without the unanimous approval of the entire Board of Directors or shareholders.   Please
summarize the type of decisions that require unanimous approval.

You may contact Gary Newberry, Staff Accountant, at (202) 551 -3761 or Kate Tillan ,
Assistant Chief  Accountant, at (202) 551 -3604 if you have questions regarding these comments.
In this regard, do not hesitate to contact me at (202) 551 -3671.

        Sincerely,

        /s/ Kate Tillan for

        Martin James
        Senior Assistant Chief Accountant