UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 3)*
Mobile Mini, Inc.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
60740F105
(CUSIP Number)
December 31, 2003
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
*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 10 pages
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CUSIP No. 60740F105 13G Page 2 of 10 Pages
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1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Columbia Wanger Asset Management, L.P. 36-3820584
--------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
Not Applicable (a) [ ]
(b) [ ]
--------------------------------------------------------------------------------
3 SEC USE ONLY
--------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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5 SOLE VOTING POWER
None
NUMBER OF SHARES ------------------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
955,000
OWNED BY
------------------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING None
PERSON WITH ------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
955,000
--------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
955,000
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
Not Applicable [ ]
--------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
6.7%
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12 TYPE OF REPORTING PERSON*
IA
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CUSIP No. 60740F105 13G Page 3 of 10 Pages
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1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
WAM Acquisition GP, Inc.
--------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
Not Applicable (a) [ ]
(b) [ ]
--------------------------------------------------------------------------------
3 SEC USE ONLY
--------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
--------------------------------------------------------------------------------
5 SOLE VOTING POWER
None
NUMBER OF SHARES ------------------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
955,000
OWNED BY
------------------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING None
PERSON WITH ------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
955,000
--------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
955,000
--------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
Not Applicable [ ]
--------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
6.7%
--------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
CO
--------------------------------------------------------------------------------
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CUSIP No. 60740F105 13G Page 4 of 10 Pages
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1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Columbia Acorn Trust
--------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
Not Applicable (a) [ ]
(b) [ ]
--------------------------------------------------------------------------------
3 SEC USE ONLY
--------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Massachusetts
--------------------------------------------------------------------------------
5 SOLE VOTING POWER
None
NUMBER OF SHARES ------------------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
825,000
OWNED BY
------------------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING None
PERSON WITH ------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
825,000
--------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
825,000
--------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
Not Applicable [ ]
--------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.7%
--------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
IV
--------------------------------------------------------------------------------
Item 1(a) Name of Issuer:
Mobile Mini, Inc.
Item 1(b) Address of Issuer's Principal Executive Offices:
7420 S. Kyrene Road, Suite 101
Tempe, Arizona 85283
Item 2(a) Name of Person Filing:
Columbia Wanger Asset Management, L.P. s1("WAM")
WAM Acquisition GP, Inc., the general partner of WAM
("WAM GP")
Columbia Acorn Trust ("Acorn")
Item 2(b) Address of Principal Business Office:
WAM, WAM GP, and Acorn are all located at:
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606
Item 2(c) Citizenship:
WAM is a Delaware limited partnership; WAM GP is a Delaware
corporation; and Acorn is a Massachusetts business trust.
Item 2(d) Title of Class of Securities:
Common Stock
Item 2(e) CUSIP Number:
60740F105
Item 3 Type of Person:
(d) Acorn is an Investment Company under section 8 of the
Investment Company Act.
(e) WAM is an Investment Adviser registered under section 203 of
the Investment Advisers Act of 1940; WAM GP is the General
Partner of the Investment Adviser.
Page 5 of 10 pages
Item 4 Ownership (at December 31, 2003):
(a) Amount owned "beneficially" within the meaning of rule
13d-3:
955,000
(b) Percent of class:
6.7 % (based on 14,348,494 shares outstanding as of November
7, 2003)
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: none
(ii) shared power to vote or to direct the vote: 955,000
(iii) sole power to dispose or to direct the disposition of:
none
(iv) shared power to dispose or to direct disposition of:
955,000
Item 5 Ownership of Five Percent or Less of a Class:
Not Applicable
Item 6 Ownership of More than Five Percent on Behalf of Another Person:
The shares reported herein have been acquired on behalf of
discretionary clients of WAM, including Acorn. Persons other than
WAM and WAM GP are entitled to receive all dividends from, and
proceeds from the sale of, those shares. Acorn is the only such
person known to be entitled to all dividends from, and all
proceeds from the sale of, shares reported herein to the extent
of more than 5% of the class.
Item 7 Identification and Classification of the Subsidiary Which Acquired the
Security Being Reported on by the Parent Holding Company:
Not Applicable
Item 8 Identification and Classification of Members of the Group:
Not Applicable
Item 9 Notice of Dissolution of Group:
Not Applicable
Page 6 of 10 pages
Item 10 Certification:
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired and are held in
the ordinary course of business and were not acquired and are not held
for the purpose of or with the effect of changing or influencing the
control of the issuer of the securities and were not acquired and are
not held in connection with or as a participant in any transaction
having that purpose or effect.
Page 7 of 10 pages
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.
Date: February 13, 2004
The undersigned corporation, on the date above written, agrees
and consents to the joint filing on its behalf of this Schedule
13G in connection with its beneficial ownership of the security
reported herein.
WAM Acquisition GP, Inc.
for itself and as general partner of
COLUMBIA WANGER ASSET MANAGEMENT, L.P.
By: /s/ Bruce H. Lauer
------------------------------------
Bruce H. Lauer
Senior Vice President and
Secretary
The undersigned trust, on the date above written, agrees and
consents to the joint filing on its behalf of this Schedule 13G
in connection with its beneficial ownership of the security
reported herein.
COLUMBIA ACORN TRUST
By: /s/ Bruce H. Lauer
------------------------------------
Bruce H. Lauer
Vice President, Treasurer and
Secretary
Page 8 of 10 pages
Exhibit Index
Exhibit 1 Joint Filing Agreement dated as of February 13, 2004 by and among
Columbia Wanger Asset Management, L.P., WAM Acquisition GP, Inc.,
and Columbia Acorn Trust.
Page 9 of 10 pages
EXHIBIT 1
JOINT FILING AGREEMENT
The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.
Dated: February 13, 2004
WAM Acquisition GP, Inc.
for itself and as general partner of
COLUMBIA WANGER ASSET MANAGEMENT,
L.P.
By: /s/ Bruce H. Lauer
------------------------------------
Bruce H. Lauer
Senior Vice President and
Secretary
COLUMBIA ACORN TRUST
By: /s/ Bruce H. Lauer
------------------------------------
Bruce H. Lauer
Vice President, Treasurer and
Secretary
Page 10 of 10 pages