SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* Horton Robert (Last) (First) (Middle) C/O BIGBAND NETWORKS, INC. 475 BROADWAY (Street) REDWOOD CITY CA 94063 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 03/14/2007	3. Issuer Name and Ticker or Trading Symbol BigBand Networks, Inc. [ BBND ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Vice Pres. & General Counsel	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Class A Convertible Common Stock	(1)	(1)	Common Stock	25,001	(2)	D
Stock option (right to buy)	(3)	03/16/2015	Common Stock	92,500	$1.32	D
Stock option (right to buy)	(4)	04/10/2016	Common Stock	75,000	$2.2	D

Explanation of Responses:

1. The convertible Class A Common Stock is covertible on a one-for-one basis upon the completion of the Initial Public Offering and has no expiration date.

2. Not applicable

3. This option vests according to the following schedule: 1/4 of the Option vests on February 1, 2006 and 1/48 of the Option vests each month thereafter.

4. This option vests according to the following schedule: 1/48 of the Option vests on May 10, 2007 and 1/48 of the Option vests each month thereafter.

	/s/ Robert Horton, by Michele Magowan, attorney in fact	03/14/2007
	** 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 5 (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).
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