<PAGE>
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
----------------------
SCHEDULE 13G
(Rule 13d-102)
INFORMATION STATEMENT PURSUANT TO RULES 13d-1 AND 13d-2
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 3)
Cubist Pharmaceuticals, Inc.
----------------------------
(Name of Issuer)
Common Stock
--------------------------------------
(Title of Class of Securities)
229678 10 7
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(CUSIP Number)
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SCHEDULE 13G
CUSIP No. 229678 10 7 Page 2 of 7
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____________________________________________________________________________
1. Name of Reporting Persons
S.S. or I.R.S. Identification Number of Above Persons
BURR, EGAN, DELEAGE & CO.
04-2681308
____________________________________________________________________________
2. Check the Appropriate Box if a Member of a Group - Not Applicable
____________________________________________________________________________
3. SEC Use Only
____________________________________________________________________________
4. Citizenship or Place of Organization
Massachusetts
____________________________________________________________________________
Number of Shares Beneficially Owned By Each Reporting Person With;
5. Sole Voting Power
N/A
____________________________________________________________________________
6. Shared Voting Power
N/A
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CUSIP No. 229678 10 7 Page 3 of 7
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- ----------------------------------------------------------------------------
7. Sole Dispositive Power
N/A
- ----------------------------------------------------------------------------
8. Shared Dispositive Power
N/A
- ----------------------------------------------------------------------------
9. Aggregate Amount Beneficially Owned by Each Reporting Person.
N/A
- ----------------------------------------------------------------------------
10. Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares.
Not Applicable
- ----------------------------------------------------------------------------
11. Percent of Class Represented by Amount in Row 9.
N/A All holdings were sold as of 8/20/99
- ----------------------------------------------------------------------------
12. Type of Reporting Person.
N/A
- ----------------------------------------------------------------------------
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CUSIP No. 229678 10 7 Page 4 of 7
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SCHEDULE 13G
Item 1(a). Name of Issuer:
- ---------------------------
Cubist Pharmaceuticasls, Inc.
Item 1(b). Address of Issuer's Principal Executive Offices:
- ------------------------------------------------------------
24 Emily St.
Cambridge, MA 02139
Item 2(a). Name of Person Filing:
- ----------------------------------
Burr, Egan, Deleage & Co.
Item 2(b). Address of
Principal Business Office or, if None, Residence:
- -------------------------------------------------
One Post Office Square
Suite 3800
Boston, MA 02109
Item 2(c). Citizenship:
- ------------------------
Massachusetts
Item 2(d). Title of Class of Securities:
- -----------------------------------------
Common Stock
Item 2(e). CUSIP Number:
- -------------------------
229678 10 7
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CUSIP No. 229678 10 7 Page 5 of 7
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Item 3:
- -------
Not Applicable
Item 4. Ownership:
- -------------------
(a) Amount Beneficially Owned:
N/A
(b) Percent of Class:
N/A
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote:
N/A
(ii) shared power to vote or to direct the vote:
N/A
(iii) sole power to dispose or to direct the
disposition of:
N/A
(iv) shared power to dispose or to direct the
disposition of:
N/A
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CUSIP No. 229678 10 7 Page 6 of 7
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Item 5. Ownership of Five Percent or Less of a Class:
- ------------------------------------------------------
Exit Filing - All Holdings Sold As Of 8/20/99
Item 6. Ownership of More Than Five Percent on Behalf of Another Person:
- -------------------------------------------------------------------------
Not Applicable
Item 7. Identification and Classification of the Subsidiary which Acquired the
Security Being Reported by the Parent Holding Company:
- -----------------------------------------------------------
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:
- ------------------------
Not Applicable
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CUSIP No. 229678 10 7 Page 7 of 7
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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.
February 9, 2000
----------------------------------
Date
Burr, Egan, Deleage & Co.
---------------------------------
/s/ Eileen McCarthy
---------------------------------
Eileen McCarthy
Vice-President
<PAGE>
ATTACHMENT A
CUBIST PHARMACEUTICALS, INC.
BURR, EGAN, DELEAGE & CO. DIRECTLY OR INDIRECTLY PROVIDES INVESTMENT ADVISORY
SERVICES TO VARIOUS VENTURE CAPITAL FUNDS, INCLUDING ALTA V LIMITED PARTNERSHIP
AND CUSTOMS HOUSE PARTNERS. AT DECEMBER 31, 1998, THE BENEFICIAL OWNERSHIP IS
AS FOLLOWS:
COMMON
SHARES
-------
ALTA V LIMITED PARTNERSHIP 976,098
CUSTOMS HOUSE PARTNERS 10,258
-------
TOTAL: 986,356
THE RESPECTIVE GENERAL PARTNERS OF THESE FUNDS EXERCISE SOLE VOTING AND
INVESTMENT POWER WITH RESPECT TO THE SHARES HELD BY SUCH FUNDS.
THE PRINCIPALS OF BURR, EGAN, DELEAGE & CO. ARE GENERAL PARTNERS OF ALTA V
MANAGEMENT PARTNERS, L.P. (THE GENERAL PARTNER OF ALTA V LIMITED PARTNERSHIP)
AND CUSTOMS HOUSE PARTNERS. AS GENERAL PARTNERS OF THE FUNDS, THEY MAY BE
DEEMED TO SHARE VOTING AND INVESTMENT POWERS FOR THE SHARES HELD BY THE FUNDS.
THESE PRINCIPALS DISCLAIM BENEFICIAL OWNERSHIP OF ALL SUCH SHARES HELD BY ALL OF
THE AFOREMENTIONED FUNDS EXCEPT TO THE EXTENT OF THEIR PROPORTIONATE PECUNIARY
INTERESTS THEREIN.
MR. TERRANCE MCGUIRE, A DIRECTOR OF THE COMPANY, IS A GENERAL PARTNER OF ALTA V
MANAGEMENT PARTNERS, L.P. (WHICH IS THE GENERAL PARTNER OF ALTAV LIMITED
PARTNERSHIP). AS GENERAL PARTNER OF THE FUND, HE MAY BE DEEMED TO SHARE VOTING
AND INVESTMENT POWERS WITH RESPECT TO THE SHARES HELD BY THE FUND. MR. MCGUIRE
DISCLAIMS BENEFICIAL OWNERSHIP OF ALL THE SHARES HELD BY ALTA V LIMITED
PARTNERSHIP EXCEPT TO THE EXTENT OF HIS PROPORTIONATE PECUNIARY INTEREST
THEREIN. MR. MCGUIRE ALSO DISCLAIMS BENEFICIAL OWNERSHIP TO ALL THE SHARES OF
CUSTOMS HOUSE PARTNERS.
MR. MCGUIRE ALSO HOLDS A DIRECTOR'S STOCK OPTION TO PURCHASE 8,542 SHARES OF
COMMON STOCK SUBJECT TO CERTAIN VESTING INSTALLMENTS.
