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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. 2 )*
OXBORO MEDICAL INTERNATIONAL, INC.
(Name of Issuer)
COMMON STOCK
(Title of Class of Securities)
691384101
(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 purposed 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 5 pages
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CUSIP NO. 691384101 13G Page 2 of 5 Pages
- ----------------------- ---------------------
- --------------------------------------------------------------------------------
NAME OF REPORTING PERSON
1 S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
HEARTLAND ADVISORS, INC.
#39-1078128
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [_]
(b) [_]
- --------------------------------------------------------------------------------
SEC USE ONLY
3
- --------------------------------------------------------------------------------
CITIZENSHIP OR PLACE OF ORGANIZATION
4
WISCONSIN, U.S.A.
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SOLE VOTING POWER
5
NUMBER OF 140,000
SHARES -------------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 6
None
OWNED BY
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EACH SOLE DISPOSITIVE POWER
7
REPORTING 140,000
PERSON -------------------------------------------------------------
SHARED DISPOSITIVE POWER
WITH 8
None
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
9
140,000
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CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10
[_]
- --------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11
5.1%
- --------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
12
IA
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CUSIP NUMBER 691384101 Page 3 Of 5 Pages
Item 1.
(a) Name of Issuer: Oxboro Medical International, Inc.
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(b) Address of Issuer's Principal Executive Offices:
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13828 Lincoln Street, N.E.
Ham Lake, MN 55304
Item 2.
(a) Name of Person Filing: Heartland Advisors, Inc.
----------------------
(b) Address of Principal Business Office:
-------------------------------------
Heartland Advisors, Inc.
790 North Milwaukee Street
Milwaukee, WI 53202
(c) Citizenship: Heartland Advisors is a Wisconsin corporation.
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(d) Title of Class of Securities: Common Stock
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(e) CUSIP Number: 691384101
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Item 3. If this statement is filed pursuant to Rule 13d-1(b),
or 13d-2(b), check whether the person filing is a:
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(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 of 1940.
(e) X 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
Sec 240.13d-1(b)(1)(ii)(F).
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(g)_____ Parent Holding Company, in accordance with
Sec 240.13d-1(b)(ii)(G) (Note: See Item 1).
(h)_____ Group, in accordance with
Sec 240.13d-1(b)(1)(ii)(H).
Item 4. Ownership.
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(a) Amount beneficially owned:
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140,000 shares may be deemed beneficially owned within the meaning of
Rule 13d-3 of the Securities Exchange Act of 1934 by Heartland Advisors, Inc.
(b) Percent of Class:
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5.1%
(c) For information on voting and dispositive power with respect to the
above listed shares, see Items 5-8 of the Cover Page.
Item 5. Ownership of Five Percent or Less of a Class.
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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:[_]
Item 6. Ownership of more than Five Percent on Behalf of Another Person.
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The shares of common stock to which this Schedule relates are held by
Heartland Limited Partnership I, a private limited partnership for which
Heartland Advisors, Inc. serves as managing general partner with voting and
dispositive power. As a result, the partnership may be deemed to have the right
to receive or the power to direct the receipt of dividends from, or the proceeds
from the sale of, the securities.
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.
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Item 10. Certification.
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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.
DATE: August 6, 1997
HEARTLAND ADVISORS, INC.
By: PATRICK J. RETZER
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Patrick J. Retzer
Senior Vice President/Treasurer
