<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 2)*
Optical Sensors, Incorporated
--------------------------------------
(Name of Issuer)
Common Stock, par value $.01 per share
--------------------------------------
(Title of Class of Securities)
68384P107
--------------
(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 68384P107 13G Page 2 of 11 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Coral Partners II, a limited partnership
SEC ID #00009245915
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [_]
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF SHARES 444,859
BENEFICIALLY -----------------------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH
REPORTING 0
PERSON -----------------------------------------------------------
WITH 7 SOLE DISPOSITIVE POWER
444,859
-----------------------------------------------------------
8 SHARED DISPOSITIVE POWER
0
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
444,859
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.998%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
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CUSIP 68384P107 13G Page 3 of 11 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Coral Management Partners II, Limited Partnership
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [_]
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF SHARES 444,859
BENEFICIALLY -----------------------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH
REPORTING 0
PERSON -----------------------------------------------------------
WITH 7 SOLE DISPOSITIVE POWER
444,859
-----------------------------------------------------------
8 SHARED DISPOSITIVE POWER
0
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
444,859
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.998%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
<PAGE>
CUSIP 68384P107 13G Page 4 of 11 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Yuval Almog
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [_]
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States (MN)
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF SHARES 989
BENEFICIALLY -----------------------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH
REPORTING 458,856
PERSON -----------------------------------------------------------
WITH 7 SOLE DISPOSITIVE POWER
989
-----------------------------------------------------------
8 SHARED DISPOSITIVE POWER
458,856
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
459,845
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.16%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
IN
- --------------------------------------------------------------------------------
<PAGE>
CUSIP 68384P107 13G Page 5 of 11 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Peter H. McNerney
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [_]
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States (MN)
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF SHARES 1,979
BENEFICIALLY -----------------------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH
REPORTING 458,856
PERSON -----------------------------------------------------------
WITH 7 SOLE DISPOSITIVE POWER
1,979
-----------------------------------------------------------
8 SHARED DISPOSITIVE POWER
458,856
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
460,835
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.18%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
IN
- --------------------------------------------------------------------------------
<PAGE>
CUSIP 68384P107 13G Page 6 of 11 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Linda L. Watchmaker
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [X]
(b) [_]
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States (MN)
- --------------------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF SHARES 343
BENEFICIALLY -----------------------------------------------------------
OWNED BY 6 SHARED VOTING POWER
EACH
REPORTING 444,859
PERSON -----------------------------------------------------------
WITH 7 SOLE DISPOSITIVE POWER
343
-----------------------------------------------------------
8 SHARED DISPOSITIVE POWER
444,859
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
445,202
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.00%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
IN
- --------------------------------------------------------------------------------
<PAGE>
Item 1. Issuer's Name and Address of Principal Executive Offices:
(a) Optical Sensors, Inc.
(b) 7615 Golden Triangle Drive, Suite A
Minneapolis, MN 55344
Item 2. Information Concerning Person Filing:
(a) Filing Persons:
Entities:
Coral Partners II, a limited partnership ("CP II")
Coral Management Partners II, Limited Partnership ("CMP II")
Individuals:
Yuval Almog
Peter H. McNerney
Linda L. Watchmaker
(b) Principal Business Address:
60 South Sixth Street
Suite 3510
Minneapolis, MN 55402
(c) Citizenship/Place of Organization
Entities:
Coral Partners II ("CP II") Delaware
Coral Management Partners II ("CMP II") Delaware
Individuals:
Yuval Almog United States
Peter H. McNerney United States
Linda L. Watchmaker United States
(d) Title of Class of Securities: Common Stock
(e) CUSIP No. 68384P107
Item 3. Status of Person Filing:
Not applicable.
Page 7 of 11
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Item 4. Ownership:
ENTITIES CP II CMP II
----- ------
(a)Beneficial Ownership 444,859 444,859*
(b)Percentage of Class 4.997% 4.997%
(c)(i)Sole Voting Power: 444,859 444,859
(ii)Shared Voting Power: 0 0
(iii)Sole Dispositive Power: 444,859 444,859
(iv)Shared Dispositive Power: 0 0
INDIVIDUALS: Almog McNerney Watchmaker
----- -------- ----------
(a)Beneficial Ownership 459,845* 460,835* 445,202*
(b)Percentage of Class 5.16% 5.18% 5.00%
(c)(i)Sole Voting Power: 989 1,979 343
(ii)Shared Voting Power: 458,856 458,856 444,859
(iii)Sole Dispositive Power: 989 1,979 343
(iv)Shared Dispositive Power: 458,856 458,856 444,859
* Pursuant to Rule 13d-4, the reporting person disclaims beneficial ownership of
these securities except to the extent of his/her pecuniary interest therein.
Item 5. Ownership of Five Percent or Less of a Class:
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 [_]X.* (The
reporting person has ceased to be the beneficial owner of more than five percent
of the class of securities).
Item 6. Ownership of More than Five Percent on Behalf of Another Person:
Not applicable.
Item 7. Identification and Classification of Subsidiary:
Not applicable.
Item 8. Identification and Classification of Group:
Not applicable.
Page 8 of 11
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Item 9. Notice of Dissolution of Group:
Not applicable.
Item 10. Certification:
Not applicable.
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.
Dated: February 7, 2000
Coral Partners II, a limited partnership
By: Coral Management Partners II, Limited Partnership,
Its: General Partner
/s/ Linda L. Watchmaker
- --------------------------------------
Linda L. Watchmaker
General Partner
Coral Management Partners II, Limited Partnership,
By: General Partner
/s/ Linda L. Watchmaker
- --------------------------------------
Linda L. Watchmaker
General Partner
By /s/ Yuval Almog
-----------------------------------
Yuval Almog
By /s/ Peter H. McNerney By /s/ Linda L. Watchmaker
----------------------------------- --------------------------------
Peter H. McNerney Linda L. Watchmaker
Page 9 of 11
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EXHIBIT INDEX
Sequentially
Exhibit Document Description Numbered Page
- ------- -------------------- -------------
A Agreement of Joint Filing 11
Page 10 of 11
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EXHIBIT A
Agreement of Joint Filing
Each of the undersigned hereby agrees that they are filing jointly pursuant
to Rule 13d-1(f)(1) of the Securities Exchange Act of 1934, as amended, the
Statement dated February 7, 2000, containing the information required by
Schedule 13G, for the shares of Common Stock of Optical Sensors, Inc. which they
each beneficially hold.
Dated: February 7, 2000
Coral Partners II, a limited partnership
By: Coral Management Partners II, Limited Partnership,
Its: General Partner
/s/ Linda L. Watchmaker
- --------------------------------------
Linda L. Watchmaker
General Partner
Coral Management Partners II, Limited Partnership,
By: General Partner
/s/ Linda L. Watchmaker
- --------------------------------------
Linda L. Watchmaker
General Partner
By /s/ Yuval Almog
-----------------------------------
Yuval Almog
By /s/ Peter H. McNerney By /s/ Linda L. Watchmaker
----------------------------------- --------------------------------
Peter H. McNerney Linda L. Watchmaker
Page 11 of 11
