SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G/A INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13d-1 (b), (c) AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2 (b) (Amendment No. 1)* TheraSense, Inc. -------------------------------------------------------------------------------- (Name of Issuer) Common Stock -------------------------------------------------------------------------------- (Title of Class of Securities) 883381105 -------------------------------------------------------------------------------- (CUSIP Number) December 31, 2004 -------------------------------------------------------------------------------- (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) [X] 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 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 pages) Page 1 of 18 Pages Exhibit Index on Page 15 ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 2 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi Ventures III, L.P. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON PN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 3 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi BioInvestments III, L.P. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON PN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 4 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi Ventures IV, L.P. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------------------------------ -------- ---------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON PN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 5 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi BioInvestments IV, L.P. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON PN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 6 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi Management Partners III, L.L.C. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON OO ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 7 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Delphi Management Partners IV, L.L.C. Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ------------ ------------------------------------------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON OO ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 8 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON James J. Bochnowski Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen ------------ ------------------------------------------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 -0- ------------------------------------ -------- ---------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON IN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 9 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON David L. Douglass Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen ------------------------------------ -------- ---------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------ ------------------------------------------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON IN ------------ ------------------------------------------------------------------- ------------------------------- ------------------- ---------------------------- CUSIP NO. 883381105 13 G Page 10 of 18 Pages ------------------------------- ------------------- ---------------------------- ------------ ------------------------------------------------------------------- 1 NAME OF REPORTING SS OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Donald J. Lothrop Tax ID Number: ------------ ------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [ ] (b) [X] ------------ ------------------------------------------------------------------- 3 SEC USE ONLY ------------ ------------------------------------------------------------------- 4 CITIZENSHIP OR PLACE OF ORGANIZATION U.S. Citizen ------------ ------------------------------------------------------------------- NUMBER OF SHARES 5 SOLE VOTING POWER BENEFICIALLY -0- OWNED BY EACH REPORTING PERSON WITH -------- ---------------------------------- 6 SHARED VOTING POWER -0- -------- ---------------------------------- 7 SOLE DISPOSITIVE POWER -0- -------- ---------------------------------- 8 SHARED DISPOSITIVE POWER -0- ------------------------------------ -------- ---------------------------------- 9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON -0- ------------ ------------------------------------------------------------------- 10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES [ ] ------------ ------------------------------------------------------------------- 11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 0.0% ------------ ------------------------------------------------------------------- 12 TYPE OF REPORTING PERSON IN ------------ ------------------------------------------------------------------- Page 11 of 18 Pages This statement amends the Statement on Schedule 13G previously filed by Delphi Ventures III, L.P., Delphi BioInvestments III, L.P., Delphi Management Partners III, L.L.C., Delphi Ventures IV, L.P., Delphi BioInvestments IV, L.P., Delphi Management Partners IV, L.L.C., James J. Bochnowski, David L. Douglass and Donald J. Lothrop. The foregoing entities and individuals are collectively referred to as the "Reporting Persons." Only those items as to which there has been a change are included in this Amendment No. 1. ITEM 4. OWNERSHIP: ---------- Please see Item 5. 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] Yes ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON: --------------------------------------------------------------- Please see Item 5. Page 12 of 18 Pages SIGNATURES 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 11, 2005 DELPHI VENTURES III, L.P., a Delaware Limited Partnership By: Delphi Management Partners III, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member DELPHI BIOINVESTMENTS III, L.P., a Delaware Limited Partnership By: Delphi Management Partners III, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member DELPHI MANAGEMENT PARTNERS III, L.L.C., a Delaware Limited Liability Company By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member Page 13 of 18 Pages DELPHI VENTURES IV, L.P., a Delaware Limited Partnership By: Delphi Management Partners IV, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member DELPHI BIOINVESTMENTS IV, L.P., a Delaware Limited Partnership By: Delphi Management Partners IV, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member DELPHI MANAGEMENT PARTNERS IV, L.L.C., a Delaware Limited Liability Company By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski, Member Page 14 of 18 Pages JAMES J. BOCHNOWSKI By: /s/ James J. Bochnowski -------------------------------------- James J. Bochnowski DAVID L. DOUGLASS By: /s/ David L. Douglass -------------------------------------- David L. Douglass DONALD J. LOTHROP By: /s/ David L. Douglass -------------------------------------- David L. Douglass Page 15 of 18 Pages EXHIBIT INDEX Found on Sequentially Exhibit Numbered Page ------- ------------- Exhibit A: Agreement of Joint Filing 16 Page 16 of 18 Pages EXHIBIT A Agreement of Joint Filing The undersigned hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Common Stock of TheraSense, Inc. shall be filed on behalf of each of the undersigned and that this Agreement shall be filed as an exhibit to such Schedule 13G. Date: February 11, 2005 February 11, 2005 DELPHI MANAGEMENT PARTNERS III, L.L.C., a Delaware Limited Liability Company By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member February 11, 2005 DELPHI VENTURES III, L.P., a Delaware Limited Partnership By: Delphi Management Partners III, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member February 11, 2005 DELPHI BIOINVESTMENTS III, L.P., a Delaware Limited Partnership By: Delphi Management Partners III, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member Page 17 of 18 Pages February 11, 2005 DELPHI MANAGEMENT PARTNERS IV, L.L.C., a Delaware Limited Liability Company By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member February 11, 2005 DELPHI VENTURES IV, L.P., a Delaware Limited Partnership By: Delphi Management Partners IV, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member February 11, 2005 DELPHI BIOINVESTMENTS IV, L.P., a Delaware Limited Partnership By: Delphi Management Partners IV, L.L.C., a Delaware Limited Liability Company Its General Partner By: /s/ James J. Bochnowski --------------------------------------- James J. Bochnowski, Member Page 18 of 18 Pages February 11, 2005 By: /s/ James J. Bochnowski ------------------------------------ James J. Bochnowski February 11, 2005 By: /s/ David L. Douglass ------------------------------------ David L. Douglass February 11, 2005 By: /s/ Donald J. Lothrop ------------------------------------ Donald J. Lothrop