EXHIBIT 1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) of the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing on behalf of each of them of a Statement on Schedule 13G (including any and all amendments thereto) with respect to the common stock, no par value per share, of Weight Watchers International, Inc and further agree that this Joint Filing Agreement shall be included as an Exhibit to such joint filing. In evidence thereof, the undersigned, being duly authorized, hereby execute this Joint Filing Agreement as of April 11, 2012.

ARTAL GROUP S.A.
By:	/s/ Anne Goffard
Name:	Anne Goffard
Title:	Authorized Person
ARTAL INTERNATIONAL S.C.A.
By: Artal International Management S.A., as its Managing Partner
By:	/s/ Anne Goffard
Name:	Anne Goffard
Title:	Managing Director
ARTAL LUXEMBOURG S.A.
By:	/s/ Anne Goffard
Name:	Anne Goffard
Title:	Managing Director