UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

Information Required In Proxy Statement

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.      )

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ARTHUR J. GALLAGHER & CO.

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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Stockholder Meeting to Be Held on May 17, 2016.

ARTHUR J. GALLAGHER & CO.

ARTHUR J. GALLAGHER & CO.

THE GALLAGHER CENTRE

TWO PIERCE PLACE

ITASCA, IL 60143-3141

Meeting Information

Meeting Type:            Annual Meeting

For holders as of:       March 23, 2016

Date:  May 17, 2016        Time:  8:30 AM EDT

Location:    Bay Adelaide Centre

    333 Bay Street

    Toronto, Ontario, Canada M5H 2T6

You are receiving this communication because you hold shares in the company named above.

This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet or by mail if you so request. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).

We encourage you to access and review all of the important information contained in the proxy materials before voting.

See the reverse side of this notice to obtain proxy materials and voting instructions.

— Before You Vote —

How to Access the Proxy Materials

	Proxy Materials Available to VIEW or RECEIVE: 1. Annual Report                 2. Notice & Proxy Statement How to View Online: Have the information that is printed in the box marked by the arrow (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request:
1) BY INTERNET:        www.proxyvote.com
2) BY TELEPHONE:    1-800-579-1639
3) BY E-MAIL*:            sendmaterial@proxyvote.com
	*  If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 3, 2016 to facilitate timely delivery.
	— How To Vote — Please Choose One of the Following Voting Methods
	Vote In Person: Please check the proxy materials for any special requirements for meeting attendance.
	Vote By Internet: To vote by Internet, go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow (located on the following page) available and follow the instructions.
	Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

        Voting Items          

The Board of Directors recommends you vote FOR the following:

1. Election of Directors

1a. Sherry S. Barrat

1b. William L. Bax

1c. D. John Coldman

1d. Frank E. English, Jr.

1e. J. Patrick Gallagher, Jr.

1f. Elbert O. Hand

1g. David S. Johnson

1h. Kay W. McCurdy

1i. Ralph J. Nicoletti

1j. Norman L. Rosenthal

The Board of Directors recommends you vote FOR proposals 2 and 3.

2. Ratification of the Appointment of Ernst & Young LLP as our Independent Auditor.

3. Approval of the Compensation of Our Named Executive Officers.

NOTE: Such other business as may properly come before the meeting or any adjournment thereof.