EXHIBIT A JOINT FILING AGREEMENT

EXHIBIT A

JOINT FILING AGREEMENT

This Joint Filing Agreement (this “Agreement”) hereby confirms the agreement by and among all of the undersigned that the Schedule 13G to which this Agreement is attached as Exhibit A with respect to the beneficial ownership of the undersigned of shares Common Stock of Westport Innovations Inc. is being filed on behalf of each of the undersigned. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

Date: February 18, 2010		* Xxxxx Xxxxxxx
		Xxxxx Xxxxxxx
Date: February 18, 2010		* Xxxxxxxx Xxxxxxx
		Xxxxxxxx Xxxxxxx
Date: February 18 2010		* Xxxxx X. Xxxxxxx III
		Xxxxx X. Xxxxxxx III
		K&M Xxxxxxx Trust
Date: February 18 2010		* Xxxxx Xxxxxxx
		By:		Xxxxx Xxxxxxx
		Title:		Trustee
Date: February 18, 2010		* Xxxxxxxx Xxxxxxx
		By:		Xxxxxxxx Xxxxxxx
		Title:		Trustee
		Xxxxxxx Family Trust
Dated: February 18, 2010		* Xxxxx X. Xxxxxxx, Xx.
		By:		Xxxxx X. Xxxxxxx, Xx.
		Title:		Trustee
Date: February 18, 2010		* Xxxx X. Xxxxxxx
		By:		Xxxx X. Xxxxxxx
		Title:		Trustee
		Xxxxx Xxxxxxx And Xxxx Xxxxxxx Irrevocable Descendants’ Trust
Date: February 18, 2010		* Xxxxx Xxxxxxx
		By:		Xxxxx Xxxxxxx
		Title:		Trustee
Date: February 18, 2010		* Xxxxxxxx Xxxxxxx
		By:		Xxxxxxxx Xxxxxxx
		Title:		Trustee

*By:		/s/ Xxxxxx Xxxxx Xxxxxxxx
		Xxxxxx Xxxxx-Xxxxxxxx
		Attorney-in-fact