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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. )*
AVECOR CARDIOVASCULAR, INC.
(Name of Issuer)
COMMON
(Title of Class of Securities)
05354710
(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).
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CUSIP No. 05354710 13G Page 2 of 5
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1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Chancellor LGT Asset Management, Inc. (94-2259541) and Chancellor LGT
Trust Company (52-1576922), as Investment Advisers for various
fiduciary accounts and LGT Asset Management, Inc. (94-303766) as the
holding company for Chancellor LGT Asset Management, Inc.
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2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [ ]
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Chancellor LGT Asset Management, Inc. - California
Chancellor LGT Trust Company - New York
LGT Asset Management, Inc. - California
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NUMBER OF SHARES 5 SOLE VOTING POWER
BENEFICIALLY OWNED BY
EACH REPORTING PERSON 909,800 shares
WITH
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6 SHARED VOTING POWER
- 0 -
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7 SOLE DISPOSITIVE POWER
909,800 shares
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8 SHARED DISPOSITIVE POWER
- 0 -
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
909,800 shares
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10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11.65%
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12 TYPE OF REPORTING PERSON*
HC, BK, IA
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CUSIP No. 05354710 Page 3 of 5
*SEE INSTRUCTIONS BEFORE FILLING OUT!
SCHEDULE 13G
Item 1. Security and Issuer
(a) AVECOR CARDIOVASCULAR, INC. (the "Company")
(b) Address: 13010 COUNTY ROAD 6
MINNEAPOLIS, MN 55441
Item 2. Identity and Background
(a) This Schedule 13G is being filed by (i) Chancellor LGT Asset
Management, Inc., a California Corporation, whose principal business is
providing investment advisory services to registered investment companies and
institutional investors, (ii) its wholly owned subsidiary, Chancellor LGT Trust
Company, a New York State chartered trust company whose principal business is
providing institutional investment management services and (iii) LGT Asset
Management, Inc., the holding company for Chancellor LGT Asset Management, Inc.
Chancellor LGT Asset Management, Inc. is a wholly owned subsidiary of LGT Asset
Management, Inc. LGT Asset Management, Inc. is an indirect wholly owned
subsidiary of Liechtenstein Global Trust, AG. Liechtenstein Global Trust, AG
which has numerous worldwide affiliates is controlled by The Prince of
Liechtenstein Foundation, a parent organization for the various business
enterprises of the Princely Family of Liechtenstein.
(b) The address of the principal place of business of Chancellor LGT
Asset Management, Inc. and Chancellor LGT Trust Company is: 1166 Avenue of the
Americas, New York, New York 10036. The address of the principal place of the
holding company, LGT Asset Management, Inc. is 50 California Street, San
Francisco, CA 94111
(c) Chancellor LGT Asset Management, Inc. is a California Corporation.
Chancellor LGT Trust Company is a New York State chartered trust company. LGT
Asset Management, Inc. is a California Corporation
(d) Common Stock
(e) CUSIP Number: 05354710
Item 3. If this statement is filed pursuant to Rule 13d-1(b) or 13d-2(b), check
whether the person filing is a:
(h) X Group, in accordance with Rule 13d-1(b)(i)(ii)(H).
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CUSIP No. 05354710 Page 4 of 5
Item 4. Ownership
(a) For the month ended APRIL 30, 1997, the aggregate number of shares
of the Company's common stock beneficially owned by Chancellor LGT Asset
Management, Inc. and Chancellor LGT Trust Company, as investment advisers for
various fiduciary accounts and LGT Asset Management, Inc., as the holding
company is 909,800 shares.
(b) Percent of Class: 11.65 based upon 7,812,000 shares outstanding.
(c) Chancellor LGT Asset Management, Inc. and Chancellor LGT Trust
Company, as investment advisers for various fiduciary accounts, have sole power
to vote or to direct to vote, and sole power to dispose of or to direct the
disposition of, all of the shares reported in this statement. Chancellor LGT
Asset Management, Inc. is a wholly owned subsidiary of LGT Asset Management,
Inc. LGT Asset Management, Inc. is an indirect wholly owned subsidiary of
Liechtenstein Global Trust, AG. Liechtenstein Global Trust, AG which has
numerous worldwide affiliates is controlled by The Prince of Liechtenstein
Foundation, a parent organization for the various business enterprises of the
Princely Family of Liechtenstein.
Item 5. Ownership of Five Percent or Less
Not applicable
Item 6. Ownership of More than Five Percent on Behalf of Another Person
Chancellor LGT Asset Management, Inc. and Chancellor LGT Trust Company
are investment advisers for various fiduciary accounts which are entitled to
receipt of dividends and to proceeds of the sale of the shares reported in this
Statement. The ownership interest of any such account does not relate to more
than five percent of the Common Stock.
Item 7. Identification and Classification of the Subsidiary Which Acquired the
Securities Being Reported by the Parent Holding Company
Not applicable.
Item 8. Identification and Classification of Members of a Group
See attached Exhibit I
Item 9. Notice of Dissolution of Group
Not applicable.
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CUSIP No. 05354710 Page 5 of 5
Item 10. Certification
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.
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: MAY 9, 1997
Signatures:
Chancellor LGT Asset Management, Inc.
as Investment Adviser
By: /s/ James R. Tufts
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James R. Tufts
Chancellor LGT Trust Company
as Investment Adviser
By: /s/ James R. Tufts
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James R. Tufts
LGT Asset Management, Inc.
as Holding Company
By: /s/ James R. Tufts
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James R. Tufts
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EXHIBIT I
Item 3
(b) X Bank as defined in Section 3(a)(b) of the Act
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Chancellor LGT Trust Company
(c) X Investment Adviser registered under Section 203 of the
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Investment Advisers Act of 1940.
Chancellor LGT Asset Management, Inc.
