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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 4)*
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Millipore Corporation
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(Name of Issuer)
Common
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(Title of Class of Securities)
601073109
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(CUSIP Number)
Check the following box if a fee is being paid with this statement / /. (A
fee is not required only if the filing person: (1) has a previous statement
on file reporting beneficial ownership of more than five percent of the class
of securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such
class.) (See Rule 13d-7.)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section
of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).
Page 1 of 8 Pages
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CUSIP No. 601073109 13G Page of Pages
--------- --- ---
- -------------------------------------------------------------------------------
(1) NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
PRIMECAP Management Company 95-3868081
- -------------------------------------------------------------------------------
(2) CHECK THE APPROPRIATE BOX IF A MEMBER (a) / /
OF A GROUP* (b) / /
- -------------------------------------------------------------------------------
(3) SEC Use Only
- -------------------------------------------------------------------------------
(4) CITIZENSHIP OR PLACE OF ORGANIZATION
225 South Lake Avenue #400, Pasadena, CA 91101-3005
- -------------------------------------------------------------------------------
NUMBER OF SHARES (5) SOLE VOTING
BENEFICIALLY POWER 1,169,170
OWNED BY --------------------------------------------------
EACH REPORTING (6) SHARED VOTING
PERSON WITH POWER -0-
--------------------------------------------------
(7) SOLE DISPOSITIVE
POWER 5,979,170
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(8) SHARED DISPOSITIVE
POWER -0-
- -------------------------------------------------------------------------------
(9) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
5,979,170
- -------------------------------------------------------------------------------
(10) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- -------------------------------------------------------------------------------
(11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
13.10%
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(12) TYPE OF REPORTING PERSON*
IA
- -------------------------------------------------------------------------------
*SEE INSTRUCTION BEFORE FILLING OUT!
Page 2 of 8 pages
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Page of Pages
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ITEM 1(A). NAME OF ISSUER
- -------------------------------------------------------------------------------
ITEM 1(B). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
- -------------------------------------------------------------------------------
ITEM 2(A). NAME OF PERSON(S) FILING
- -------------------------------------------------------------------------------
ITEM 2(B). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
- -------------------------------------------------------------------------------
ITEM 2(C). CITIZENSHIP
- -------------------------------------------------------------------------------
ITEM 2(D). TITLE OF CLASS OF SECURITIES
- -------------------------------------------------------------------------------
ITEM 2(E). CUSIP NUMBER
- -------------------------------------------------------------------------------
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B),
CHECK WHETHER THE PERSON FILING IS A
(a) / / Broker or Dealer registered under Section 15 of the Act
(b) / / Bank as defined in section 3(a)(6) of the Act
(c) / / Insurance Company as defined in section 3(a)(19) of the Act
(d) / / Investment Company registered under section 8 of the Investment
Company Act
(e) / / Investment Adviser registered under section 203 of the Investment
Advisers Act of 1940
(f) / / Employee Benefit Plan, Pension Fund which is subject to the
provisions of the Employee Retirement Income Security Act of 1974
or Endowment Fund; see Rule 13d-1(b)(1)(ii)(F)
(g) / / Parent Holding Company, in accordance with Rule 13d-1(b)(ii)(G)
(Note: See Item 7)
(h) / / Group, in accordance with Rule 13d-1(b)(1)(ii)(H)
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Page of Pages
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ITEM 4. OWNERSHIP
(a) Amount Beneficially Owned:
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(b) Percent of Class:
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(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote
(ii) shared power to vote or to direct the vote
(iii) sole power to dispose or to direct the disposition of
(iv) shared power to dispose or to direct the disposition of
INSTRUCTION: For computations regarding securities which represent a right to
acquire an underlying security see Rule 13d-3(d)(1).
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more
than five percent of the class of securities, check the following / /.
INSTRUCTION: Dissolution of a group requires a response to this item.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
If any other person is known to have the right to receive or the power to
direct the receipt of dividends from, or the proceeds from the sale of, such
securities, a statement to that effect should be included in response to this
item and, if such interest relates to more than five percent of the class,
such person should be identified. A listing of the shareholders of an
investment company registered under the Investment Company Act of 1940 or the
beneficiaries of employee benefit plan, pension fund or endowment fund is not
required.
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
If a parent holding company has filed this schedule, pursuant to Rule
13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating
the identity and the Item 3 classification of the relevant subsidiary. If a
parent holding company has filed this schedule pursuant to Rule 13d-1(c),
attach an exhibit stating the identification of the relevant subsidiary.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
If a group has filed this schedule pursuant to Rule 13d-1(b)(ii)(H), so
indicate under Item 3(h) and attach an exhibit stating the identity and Item
3 classification of each member of the group. If a group has filed this
schedule pursuant to Rule 13d-1(c), attach an exhibit stating the identity of
each member of the group.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
Notice of dissolution of a group may be furnished as an exhibit stating
the date of the dissolution and that all further filings with respect to
transactions in the security reported on will be filed, if required, by
members of the group, in their individual capacity. See Item 5.
ITEM 10. CERTIFICATION
The following certification shall be included if the statement is filed
pursuant to Rule 13d-1(b):
By signing below I certify that, to the best of my knowledge and belief,
the securities referred to above were acquired in the ordinary course of
business and were not acquired for the purpose of and do not have the effect of
changing or influencing the control of the issuer of such securities and were
not acquired in connection with or as a participant in any transaction having
such purposes or effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
February 29, 2000
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Date
/s/ Theo A. Kolokotrones
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Signature
Theo A. Kolokotrones, President
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Name/Title
Page 5 of 8 pages
