Exhibit 5
4365 Executive Drive, Suite 1100, San Diego, CA 92121
Phone: 858-677-1400 Fax: 858-677-1401 www.dlapiper.com
May 15, 2007
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
Ladies and Gentlemen:
As legal counsel for Jack in the Box Inc., a Delaware corporation (the Company), we are rendering
this opinion in connection with the registration under the Securities Act of 1933, as amended, of
up to 100,000 shares of the Common Stock, $0.01 par value, of the Company which may be issued
pursuant to the Amended and Restated Jack in the Box Inc. Deferred Compensation Plan for
Non-Management Directors (the Plan).
We have examined all instruments, documents and records which we deemed relevant and necessary for
the basis of our opinion hereinafter expressed. In such examination, we have assumed the
genuineness of all signatures and the authenticity of all documents submitted to us as originals
and the conformity to the originals of all documents submitted to us as copies. We express no
opinion concerning any law other than the corporation laws of the State of Delaware. As to matters
of Delaware corporation law, we have based our opinion solely upon our examination of such laws and
the rules and regulations of the authorities administering such laws, all as reported in standard,
unofficial compilations.
Based on such examination, we are of the opinion that the 100,000 shares of Common Stock which may
be issued under the Plan are duly authorized shares of the Companys Common Stock, and, when issued
against receipt of the consideration therefor in accordance with the provisions of the Plan, will
be validly issued, fully paid and nonassessable. We hereby consent to the filing of this opinion
as an exhibit to the Registration Statement referred to above and the use of our name wherever it
appears in said Registration Statement.
Respectfully submitted,
/s/ DLA Piper US LLP
DLA PIPER US LLP