Washington, D.C. 20549

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person Authorized to
Receive Notices and Communications)

(Date of Event Which Requires Filing of this Statement)

 

 

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     This Amendment No. 9 to Schedule 13D (this “Amendment No. 9”) relates to the common shares, without par value (the “Common Shares”), of Keithley Instruments, Inc., an Ohio corporation (the “Company”), and is primarily filed to reflect changes to the initial Schedule 13D dated April 12, 1988 (the “Original 13D”), as amended by Amendment No. 1 to Schedule 13D dated February 5, 1990 (“Amendment No. 1”), Amendment No. 2 to Schedule 13D dated March 9, 1991 (“Amendment No. 2”), Amendment No. 3 to Schedule 13D dated November 15, 1997 (“Amendment No. 3”), Amendment No. 4 to Schedule 13D dated February 27, 2004 (“Amendment No. 4”), Amendment No. 5 to Schedule 13D dated March 9, 2009 (“Amendment No. 5”), Amendment No. 6 to Schedule 13D dated March 12, 2009 (“Amendment No. 6”), Amendment No. 7 to Schedule 13D dated December 8, 2009 (“Amendment No. 7”), and Amendment No. 8 to Schedule 13D dated April 9, 2010 (“Amendment No. 8” and, together with Amendment No. 1, Amendment No. 2, Amendment No. 3, Amendment No. 4, Amendment No. 5, Amendment No. 6 and Amendment No. 7, the “Prior Amendments”). Except as otherwise reflected in this Amendment No. 9, there have been no material changes to the information contained in the Original 13D, as amended by the Prior Amendments.

ITEM 4. PURPOSE OF TRANSACTION.

     Item 4 of the Schedule 13D is hereby amended as follows:

     On September 29, 2010, the Company entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Danaher Corporation (“Danaher”) and Aegean Acquisition Corp., an indirect wholly-owned subsidiary of Danaher (“Merger Sub”). The Merger Agreement provides that, upon the terms and subject to the conditions set forth in the Merger Agreement, the Company will merge with and into Merger Sub, with the Company continuing as the surviving corporation and an indirect wholly-owned subsidiary of Danaher (the “Merger”). At the effective time and as a result of the Merger, each Common Share and Class B Share will be converted into the right to receive $21.60 per share in cash payable by Danaher.

     The Family Partnership has agreed to vote in favor of the Merger.

     The foregoing description of the Merger Agreement is qualified in its entirety by reference to the full text of the Merger Agreement, which is filed as Exhibit 2 hereto, and is incorporated herein by reference.

     The information set forth in Item 6 is hereby incorporated by reference into this Item 4.

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

     Item 5 of the Schedule 13D is hereby amended as follows:

     The following table shows the number and percentage of Common Shares beneficially owned by each of the Investors and by the Investors as a group as of September 29, 2010.

Name		Common Shares				Percent of Class
Family Partnership			1,954,816	(1)			12.38	%
Joseph P. Keithley			2,741,724	(2)			16.85	%
Investors as a group			2,741,724				16.85	%

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     Except as otherwise described in this Amendment No. 9, the Investors have not engaged in any transactions in the Common Shares or the Class B Shares in the past 60 days.

ITEM 6. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO SECURITIES OF THE ISSUER

     Item 6 of the Schedule 13D is hereby amended as follows:

     The Family Partnership has entered into a Voting Agreement, dated as of September 29, 2010, with Danaher and Merger Sub (the “Voting Agreement”) pursuant to which the Family Partnership has agreed to vote (or cause to be voted) in favor of the adoption of the Merger Agreement such number of its Class B Shares (or any Common Shares, Class B Shares or other voting securities of the Company that the Family Partnership acquires beneficial ownership of after September 29, 2010) that as of the relevant time shall equal 19.99% of the voting power (as such term is used in Chapter 1701 of the Ohio Revised Code) of the Company (the “Subject Shares”). In addition, the Family Partnership agreed to vote (or cause to be voted) the Subject Shares against (i) any proposal that would result in a breach by the Company of the Merger Agreement, or (ii) any action or agreement that is intended to, or would be reasonably likely to, impede, interfere with, delay, postpone or attempt to discourage the Merger, including, but not limited to: (A) the adoption or approval by the Company of any Company Takeover Proposal (as defined in the Merger Agreement); (B) any amendment of the Company’s articles of incorporation or code of regulations; (C) any material change in the present capitalization or dividend policy of the Company; or (D) any other material change in the Company’s corporate structure or business. The Family Partnership also granted Merger Sub an irrevocable proxy to vote the Subject Shares on the foregoing matters.

     The Family Partnership also agreed not to sell, transfer, pledge, assign or otherwise dispose of its shares or enter into any other voting agreement or convert the Family Partnership’s Class B Shares into Common Shares. These obligations terminate upon the earlier of the termination of the Merger Agreement or the Effective Time (both as indicated in the Merger Agreement) or, at the option of the Family Partnership, the execution or granting of any amendment, modification, change or waiver with respect to the Merger Agreement that results in any decrease in the price to be paid per share for the Common Shares and/or Class B Shares or any changes in the form of consideration to be received by the holders of such shares in the Merger or is otherwise adverse to the shareholders of the Company.

     The foregoing description of the Voting Agreement is qualified in its entirety by reference to the full text of the Voting Agreement, which is filed as Exhibit 3 hereto, and is incorporated herein by reference.

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ITEM 7. MATERIAL TO BE FILED AS EXHIBITS

1.		Agreement among the Investors to file a joint statement on Schedule 13D
2.		Agreement and Plan of Merger, dated September 29, 2010, by and among Danaher, the Company and Merger Sub, which is incorporated herein by reference to Exhibit 2.1 to the Company’s Current Report on Form 8-K, filed by the Company on September 29, 2010
3.		Voting Agreement, dated September 29, 2010, by and among Danaher, Merger Sub and Keithley Investment Co. Limited Partnership, which is incorporated herein by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K, filed by the Company on September 29, 2010

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SIGNATURES

     After reasonable inquiry and to the best of his or its knowledge and belief, each of the undersigned hereby certifies that the information set forth in this statement is true, complete and correct as of October 5, 2010.