1. Name and Address of Reporting Person * Matte Dan	2. Date of Event Requiring Statement (MM/DD/YYYY) 6/1/2004	3. Issuer Name and Ticker or Trading Symbol F5 NETWORKS INC [FFIV]
(Last)        (First)        (Middle) C/O F5 NETWORKS, INC., 401 ELLIOTT AVENUE WEST	4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                            _____ 10% Owner ___ X ___ Officer (give title below)          _____ Other (specify below) Sr. VP of Marketing /
(Street) SEATTLE, WA 98119        (City)              (State)              (Zip)	5. If Amendment, Date Original Filed (MM/DD/YYYY)	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)
Common Stock	5938	D

Table II - Derivative Securities Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: 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
Non-Qualified Stock Option (right to buy)   (1)	3/26/1999	3/26/2009	Common Stock	2375   (6)	$8	D
Non-Qualified Stock Option (right to buy)   (2)	1/1/2002	1/1/2011	Common Stock	11000   (6)	$9.5	D
Non-Qualified Stock Option (right to buy)   (3)	5/27/2001	4/27/2011	Common Stock	2000   (6)	$7	D
Non-Qualified Stock Option (right to buy)   (3)	6/6/2002	5/6/2012	Common Stock	15000   (6)	$11.12	D
Non-Qualified Stock Option (right to buy)   (4)	6/8/2003	5/8/2013	Common Stock	14000   (6)	$14.64	D
Non-Qualified Stock Option (right to buy)   (4)	8/18/2003	7/18/2013	Common Stock	30000   (6)	$17.16	D
Non-Qualified Stock Option (right to buy)   (5)	4/30/2005	4/30/2014	Common Stock	7000   (6)	$25.49	D

Explanation of Responses:
(1)	Options vested 50% on the date of grant and the remaining amount vested monthly over the following four years.
(2)	Options vested 50% one year following the date of grant and the remaining 50% vested two years following the date of grant.
(3)	Options vested in equal monthly increments over the two year period following the date of grant.
(4)	Options vest in equal monthly increments over the two year period following the date of grant.
(5)	Options vest 100% one year following the date of grant.
(6)	Indicates the number of options outstanding as of June 1, 2004.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Matte Dan C/O F5 NETWORKS, INC. 401 ELLIOTT AVENUE WEST SEATTLE, WA 98119			Sr. VP of Marketing

Signatures
/s/ Dan Matte		6/3/2004
** 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 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).
Note:	File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.