SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
X	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* C4S & CO LLC (Last) (First) (Middle) 666 THIRD AVENUE 26TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol REDBACK NETWORKS INC [ RBAKD ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 01/07/2004
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock, par value $.0001 per share ("Common Stock")	01/07/2004		S		8,510	D	$8.6401	145,784	I(1)	See(1)
Common Stock	01/07/2004		S		142,740	D	$8.6401	2,445,324	I(2)	See(2)
Common Stock	01/07/2004		S		18,361	D	$8.6401	314,544	I(3)	See(3)
Common Stock	01/07/2004		S		8,456	D	$8.6401	144,871	I(4)	See(4)
Common Stock	01/07/2004		S		10,637	D	$8.6401	182,228	I(5)	See(5)
Common Stock	01/07/2004		S		81,403	D	$8.6401	1,394,539	I(6)	See(6)
Common Stock	01/07/2004		S		7,713	D	$8.6401	132,132	I(7)	See(7)
Common Stock	01/07/2004		S		2,052	D	$8.6401	35,159	I(8)	See(8)
Common Stock	01/07/2004		S		5,128	D	$8.6401	87,855	I(9)	See(9)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* C4S & CO LLC (Last) (First) (Middle) 666 THIRD AVENUE 26TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* STARK MORGAN B (Last) (First) (Middle) 666 THIRD AVENUE 26TH FLOOR (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* STRAUSS THOMAS W (Last) (First) (Middle) 666 THIRD AVE 26TH FL (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* COHEN PETER A (Last) (First) (Middle) 666 THIRD AVE 26TH FL (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* SOLOMON JEFFREY M (Last) (First) (Middle) 666 THIRD AVENUE 26TH FL (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. These securities are owned directly by Xavex Covertible Arbitrage Fund 5. Ramius Capital Group, LLC is the investment advisor of Xavex Covertible Arbitrage Fund 5. Therefore, the Reporting Persons may be deemed to indirectly own these securities. Each of the Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by Xavex Covertible Arbitrage Fund 5 to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

2. These securities are owned directly by RCG Latitude Master Fund, Ltd. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by RCG Latitude Master Fund, Ltd. to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

3. These securities are owned directly by Ramius Securities, LLC. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by Ramius Securities, LLC to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

4. These securities are owned directly by RCG Halifax Fund, Ltd. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by RCG Halifax Fund, Ltd. to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

5. These securities are owned directly by RCG Multi-Strategy Master Fund, Ltd. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by RCG Multi-Strategy Master Fund, Ltd. to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

6. These securities are owned directly by Ramius Master Fund, Ltd. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by Ramius Master Fund, Ltd. to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

7. These securities are owned directly by Guggenheim Portfolio Company XV, LLC. Ramius Capital Group, LLC is the investment advisor of Guggenheim Portfolio Company XV, LLC. Therefore, the Reporting Persons may be deemed to indirectly own these securities. Each of the Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by Guggenheim Portfolio Company XV, LLC to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

8. These securities are owned directly by Ramius, LP. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by Ramius, LP to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

9. These securities are owned directly by RCG Baldwin, LP. The other Reporting Persons may be deemed to indirectly own these securities as members of a Section 13(g) group. Each of the other Reporting Persons disclaims any beneficial ownership of the shares of Common Stock owned by RCG Baldwin, LP to the extent such beneficial ownership exceeds such Reporting Person's pecuniary interest.

Remarks:

Part 2 of 2

	C4S & CO., L.L.C. By Morgan B. Stark, as Man. Mbr. /s/ Morgan B. Stark	01/09/2004
	MORGAN B. STARK, /s/ Morgan B. Stark	01/09/2004
	THOMAS W. STRAUSS, /s/ Thomas W. Strauss	01/09/2004
	PETER A. COHEN, /s/ Peter A. Cohen	01/09/2004
	JEFFREY M. SOLOMON, /s/ Jeffrey M. Solomon	01/09/2004
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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