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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C 20549
SCHEDULE 13G/A-15
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 15)*
DIAGNOSTIC PRODUCTS CORPORATION
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(Name of Issuer)
COMMON STOCK, NO PAR VALUE
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(Title of Class of Securities)
252450-10-1
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(CUSIP Number)
DECEMBER 31, 1999
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(Date of Event which Requires Filing 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)
[X] Rule 13d-1(d)
*The remainder of this cover page shall be filed 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).
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CUSIP NO. 252450-10-1 13G
1. NAME OF REPORTING PERSON
S.S OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
SIGI ZIERING
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP.
(A) [X]
(B) [ ]
3. SEC USE ONLY
4. CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.A.
NUMBER OF 5. SOLE VOTING POWER: 2,425,706
SHARES
BENEFICIALLY 6. SHARED VOTING POWER: 18,200
OWNED BY
EACH REPORTING 7. SOLE DISPOSITIVE POWER: 2,425,706
PERSON WITH
8. SHARED DISPOSITIVE POWER: 18,200
9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,443,906
10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
[ ]
11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
17.9%
12. TYPE OF REPORTING PERSON
IN
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CUSIP NO. 252450-10-1 13G
1. NAME OF REPORTING PERSON
S.S OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
MARILYN ZIERING
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP.
(A) [X]
(B) [ ]
3. SEC USE ONLY
4. CITIZENSHIP OR PLACE OF ORGANIZATION
U.S.A.
NUMBER OF 5. SOLE VOTING POWER: 2,425,706
SHARES
BENEFICIALLY 6. SHARED VOTING POWER: 18,200
OWNED BY
EACH REPORTING 7. SOLE DISPOSITIVE POWER: 2,425,706
PERSON WITH
8. SHARED DISPOSITIVE POWER: 18,200
9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,443,906
10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
[ ]
11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
17.9%
12. TYPE OF REPORTING PERSON
IN
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Item 1(a) Name of Issuer: Diagnostic Products Corporation
Item 1(b) Address of Issuer's Principal Executive Offices:
5700 West 96th Street
Los Angeles, California 90045
Item 2(a) Name of Persons Filing:
Sigi Ziering and Marilyn Ziering, husband and wife
Item 2(b) Address of Principal Office: 5700 West 96th Street
Los Angeles, CA 90045
Item 2(c) Citizenship: U.S.A.
Item 2(d) Title of Class of Securities: Common Stock
Item 2(e) CUSIP Number: 252450-10-1
Item 3 Statement filed Pursuant to Rules 13d-1(b) or 13(d)-2(b) or (c):
Not Applicable
Item 4(a) Amount Beneficially Owned: 2,425,706 shares are owned by Sigi Ziering
and Marilyn Ziering as husband and wife. 18,200 shares are owned by
the mother of Sigi Ziering who resides with Mr. and Mrs. Ziering, as
to which shares beneficial ownership is disclaimed. Based on the
foregoing, Sigi Ziering and Marilyn Ziering beneficially own an
aggregate of 2,443,906 shares.
Item 4(b) Percent of Class: 17.9%.
Item 4(c) For information regarding the number of shares as to which each
reporting person has voting and dispositive power, see Items 5-8 of
the cover pages hereto.
Item 5 Ownership of 5% or Less of Class: Not Applicable
Item 6 Ownership of More than 5% on Behalf of Another Person:
Not Applicable
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: The members
of the group are Sigi Ziering and Marilyn Ziering, husband and wife.
Item 9 Notice of Dissolution of Group: Not Applicable
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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.
Pursuant to Rule 13d-1(k)(1), the undersigned agree that this statement is
filed on behalf of each of them.
Dated: February 1, 2000 /s/ Sigi Ziering
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Sigi Ziering
/s/ Marilyn Ziering
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Marilyn Ziering
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