SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
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SCHEDULE 13G
(Rule 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO RULE 13d-1(b)(c), AND (d) AND AMENDMENTS THERETO FILED
PURSUANT TO RULE 13d-2(b)
(Amendment No. 10)(1)
Bio-Logic Systems Corp.
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(Name of Issuer)
Common Stock, $.01 par value
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(Title of Class of Securities)
090909 10 2
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(CUSIP Number)
December 31, 1999
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(Date of Event which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which
this Schedule is filed:
|_| Rule 13d-1 (b)
|_| Rule 13d-1 (c)
|_| Rule 13d-1 (d)
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(1) 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 disclosures provided in a prior cover page.
The information required on 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).
(Continued on following page(s))
Page 1 of 4 Pages
<PAGE>
CUSIP No. 090909 10 2 SCHEDULE 13G Page 2 of 4 Pages
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1 NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Charles Z. Weingarten, M.D.
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) |_|
(b) |_|
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States
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5 SOLE VOTING POWER
241,101
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NUMBER OF 6 SHARED VOTING POWER
SHARES
BENEFICIALLY -0-
OWNED BY --------------------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
REPORTING
PERSON 241,101
WITH --------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
-0-
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
241,101
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES*
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.0%
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12 TYPE OF REPORTING PERSON*
IN
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*SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
CUSIP No. 090909 10 2 SCHEDULE 13G Page 3 of 4 Pages
Item 1(a). Name of Issuer: Bio-Logic Systems Corp.
Item 1(b). Address of Issuer's Principal Executive Offices: One Bio-Logic Plaza,
Mundelein, IL 60060
Item 2(a). Name of Person Filing: See Item 1 on page 2
Item 2(b). Address of Principal Business Office or if none, Residence: See item
1(b) above
Item 2(c). Citizenship: See item 4 on page 2
Item 2(d). Title of Class of Securities: Common Stock, $.01 par value
Item 2(e). CUSIP Number: 090909 10 2
Item 3. Not Applicable
Item 4. Ownership:
(a) Amount Beneficially Owned: As of December 31, 1999, Dr. Weingarten
beneficially owned 241,101 shares of the issuer's Common Stock, which includes
12,500 shares underlying options exercisable within 60 days. Does not include
(i) 9,000 shares owned by his children, as to which he disclaims beneficial
ownership; (ii) 40,000 shares owned by a corporation of which he has 22% voting
power or (iii) shares underlying options which are not exercisable within 60
days.
(b) Percent of Class: 6.0%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote: 241,101
(ii) shared power to vote or to direct the vote: -0-
(iii) sole power to dispose or to direct the disposition of: 241,101
(iv) shared power to dispose or to direct the disposition of: -0-
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: Not
Applicable
Item 7. Identification and Classification of Subsidiary Which Acquired the
Securities: Not Applicable
Item 8. Identification and Classification of Members of the Group: Not
Applicable
<PAGE>
CUSIP No. 090909 10 2 SCHEDULE 13G Page 4 of 4 Pages
Item 9. Notice of Dissolution of Group Not Applicable
Item 10. Certification: Not Applicable
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 11, 2000
By: /s/ Charles Z. Weingarten
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Charles Z. Weingarten, M.D.
