As filed with the Securities and Exchange Commission on June 4, 2010

No. 333-140362

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Post-Effective Amendment No. 4

on

Form S-8

To

Form S-4

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

PROTECTION ONE, INC.

(Exact name of registrant as specified in its charter)

Integrated Alarm Services Group, Inc. 2003 Stock Option Plan

Integrated Alarm Services Group, Inc. 2004 Stock Incentive Plan

(Full title of the plan)

J. Eric Griffin, Esq.

General Counsel

4221 West John Carpenter Freeway

Irving, TX 75063

(Name and address of agent for service)

(785) 856-5500
(Telephone number, including area code, of agent for service)

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company.  See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

EXPLANATORY NOTE

Protection One, Inc. (the “Company”) filed a Post-Effective Amendment No. 3 on Form S-8 to Form S-4 (No. 333-140362) (“PE Amendment No. 3”) with the Securities and Exchange Commission on October 26, 2007, to register on Form S-8 shares of common stock , par value $.01 per share (the “Common Stock”) previously registered on Form S-4 .  On June 4, 2010, pursuant to that certain Agreement and Plan of Merger, dated as of April 26, 2010, by and among the Company, Protection Acquisition Sub, Inc., a Delaware corporation, and Protection Holdings, LLC, a Delaware limited liability company (“Holdings”) (as amended by that certain Amendment No. 1 to the Agreement and Plan of Merger dated May 21, 2010), the registrant will become an indirect wholly owned subsidiary of Holdings.  As a result of the transactions contemplated thereby, the Company has terminated all offerings of the Company’s securities pursuant to PE Amendment No. 3.

This Post-Effective Amendment No. 4 is being filed to deregister, as of the effectiveness of this post-effective amendment, all unsold shares of Common Stock , the sale of which was registered under PE Amendment No. 3.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Irving, State of Texas, on the 4th day of June, 2010.

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