UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a)

of the Securities Exchange Act of 1934

(Rule 14a-101)

Filed by the Registrant þ

Filed by a Party other than the Registrant o

Check the appropriate box:

o Preliminary Proxy Statement

o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

o Definitive Proxy Statement

þ Definitive Additional Materials

o Soliciting Material Pursuant to §240.14a-12

MILLIPORE CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

þ		No fee required.
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	(3)		Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
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	(5)		Total fee paid:

o		Fee paid previously with preliminary materials.
o		Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
	(1)		Amount Previously Paid:
	(2)		Form, Schedule or Registration Statement No.:
	(3)		Filing Party:
	(4)		Date Filed:

On May 10, 2010, the following letter was mailed to Millipore stockholders.

IMPORTANT REMINDER

PLEASE VOTE YOUR PROXY TODAY

May 10, 2010

Dear Shareholder:

We have previously mailed you proxy materials in connection with the Special Meeting of Shareholders of Millipore Corporation, to be held on June 3, 2010.  According to our latest records, we have not yet received your proxy for this important meeting.  Your vote is important.  Telephone and Internet voting are available for your convenience.

At the special meeting, shareholders are being asked to consider and vote upon a proposal to approve the Agreement and Plan of Share Exchange, dated as of February 28, 2010 (the “exchange agreement”), by and among Millipore, Merck KGaA and Concord Investments Corp., pursuant to which each outstanding share of Millipore’s common stock, par value $1.00 per share (the “common stock”) will be transferred by operation of law to Concord Investments Corp. in exchange for the right to receive $107.00 per share in cash, without interest (such transaction, the “exchange”).

Consummation of the exchange requires the approval of the exchange agreement by holders of at least 66-2/3% of our outstanding common stock. If you fail to vote on the exchange agreement, such failure to vote will have the same effect as voting against the approval of the exchange agreement.  Accordingly, please vote your proxy today without further delay.

Our Board of Directors recommends that you vote “FOR” approval of the exchange agreement and “FOR” approval of the adjournment or postponement of the special meeting to a later date or time, if necessary or appropriate.

If you have any questions or need assistance voting your proxy, please call D. F. King & Co., Inc., which is assisting us, toll-free at 1-800-628-8532.

Thank you for voting and for your cooperation and continued support.

Dr. Martin D. Madaus

Chairman of the Board of Directors, President and

Chief Executive Officer