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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No._________________)*
DIAMETRICS MEDICAL, INC.
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(Name of Issuer)
COMMON STOCK, $.01 PAR VALUE PER SHARE
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(Title of Class of Securities)
252532106
-------------------
(CUSIP Number)
August 4, 1998
-----------------------------
(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)
[x] 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 disclosure
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).
Page 1 of 6 Pages
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<TABLE>
<CAPTION>
- ----------------------------------
CUSIP NO. 252532106 13G
- ----------------------------------
<S><C>
- ---------------------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
AMARFOUR, L.L.C.
- ---------------------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) |_|
(b) |_|
- ---------------------------------------------------------------------------------------------
3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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5 SOLE VOTING POWER
1,789,100 Shares of Common Stock
NUMBER
OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON
WITH:
------------------------------------------------------------------------
6 SHARED VOTING POWER
0
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7 SOLE DISPOSITIVE POWER
1,789,100 Shares of Common Stock
------------------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
0
- ---------------------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,789,100 Shares of Common Stock
- ---------------------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
See Item 5 below. X
- ---------------------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9).
Approximately 7.7%
- ---------------------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON
OO
- ---------------------------------------------------------------------------------------------
</TABLE>
Page 2 of 6 Pages
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Item 1(a) Name of Issuer
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Diametrics Medical, Inc., a Minnesota corporation
Item 1(b) Address of Issuer's Principal Executive Offices
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2658 Patton Road
Roseville, Minnesota 55113
Item 2(a) Name of Person Filing
---------------------
Amarfour, L.L.C.
Item 2(b) Address of Principal Business Office or, if none, Residence
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200 West Madison Street
Suite 3800
Chicago, Illinois 60606
Item 2(c) Citizenship
-----------
Delaware
Item 2(d) Title of Class of Securities
----------------------------
Common Stock, $.01 par value per share (the "Common Stock")
Item 2(e) CUSIP Number
------------
252532106
Item 3 If this Statement is Filed Pursuant to
Section 240.13d-1(b) or Section 240.13d-2(b) or (c)
---------------------------------------------------
Not Applicable
If this Statement is Filed Pursuant to
Section 240.13d-1(c), check this box.
-------------------------------------
X
Item 4 Ownership
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(a) Amount Beneficially Owned as of August 4, 1998:
1,789,100 shares of Common Stock
Page 3 of 6 Pages
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(b) The Reporting Person has been advised by the Issuer that
the total number of shares of Common Stock issued and
outstanding as of August 4, 1998 was 23,332,781.
(c) As of the date hereof, the Reporting Person may be deemed
to beneficially own the 1,789,100 shares of Common Stock
or, to the best of its knowledge, approximately 7.7% of
the issued and outstanding shares of Common Stock.
(d) As previously reported by the Reporting Person, and as
of August 4, 1998, an affiliate of the Reporting Person
(the "RA Trusts") directly owned 25,319 shares of Common
Stock of the Issuer (or approximately .11% of the
outstanding Common Stock of the Issuer). In addition,
the Reporting Person has been advised that: (a) as of
August 4, 1998, the RA Trusts owned indirect interests
in each of BCC Acquisition II LLC, The Bay City Capital
Fund I, L.P., Bay City Capital Management LLC and Bay
City Capital LLC (collectively, the "Bay City
Entities"); (b) as of August 4, 1998, the Bay City
Entities acquired beneficial ownership of up to an
aggregate of 3,400,540 shares of the Issuer's Common
Stock (or approximately 13.7% of the Issuer's Common
Stock); (c) as of August 4, 1998 certain trusts
primarily for the benefit of the lineal descendants of
Nicholas J. Pritzker, deceased (the "Hoinfad Trusts")
owned less than a 10% interest in AEOW 96, LLC ("AEOW");
(d) as of August 4, 1998, AEOW acquired beneficial
ownership of an additional 30,953 shares of the Issuer's
Common Stock, and, as of such date, beneficially owned
an aggregate of 91,042 shares of the Issuer's Common
Stock (or approximately .39% of the Issuer's Common
Stock); (e) different individuals serve as trustees of
the member trusts of the Reporting Person and the RA
Trusts on the one hand and the Hoinfad Trusts on the
other hand, and there is no overlap in trusteeships
between the Hoinfad Trusts and the member trusts of the
Reporting Person, but there is overlap in trusteeships
between the member trusts of the Reporting Person and
the RA Trusts; (f) none of the Reporting Person, its
member trusts, the RA Trusts, the Hoinfad Trusts, AEOW
or the Bay City Entities have any express or implied
agreement to act together for the purpose of acquiring,
holding, voting or disposing of the Issuer's Common
Stock or any other securities of the Issuer; and (g) the
Reporting Person expressly disclaims (i) the existence
of any group with any or all of the RA Trusts, the
Hoinfad Trusts, AEOW or the Bay City Entities, and (ii)
beneficial ownership of the shares of the Issuer's
Common Stock or any other securities of the Issuer
currently or hereafter owned by any or all of the RA
Trusts, the Hoinfad Trusts, AEOW or the Bay City
Entities.
Page 4 of 6 Pages
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Item 5 Ownership of Five Percent or Less of a Class
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Not Applicable
Item 6 Ownership of More Than Five Percent on Behalf of Another
Person
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Not Applicable
Item 7 Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported on by the Parent Holding
Company
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Not Applicable
Item 8 Identification and Classification
of Members of the Group
-----------------------
Not Applicable
Item 9 Notice of Dissolution of Group
------------------------------
Not Applicable
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 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 5 of 6 Pages
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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 14, 1998
AMARFOUR, L.L.C., a Delaware limited
liability company
By: AMARILLO RESIDUARY TRUST NO. 1, a member
By: /s/ Marshall E. Eisenberg
-----------------------------------------
Marshall E. Eisenberg, not individually,
but solely as Trustee of Amarillo Residuary
Trust No. 1
Page 6 of 6 Pages
