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

1. Name and Address of Reporting Person * Lin Geng	2. Issuer Name and Ticker or Trading Symbol F5 NETWORKS, INC. [ FFIV ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) EVP, Chief Technology Officer
(Last)          (First)          (Middle) C/O F5 NETWORKS, INC., 801 5TH AVENUE	3. Date of Earliest Transaction (MM/DD/YYYY) 11/1/2021
(Street) SEATTLE, WA 98104 (City)        (State)        (Zip)	4. 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 Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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	11/1/2021		M		2531 (1)	A	$0.00	12251	D
Common Stock	11/1/2021		F		3210	D	$0.00	9041	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		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 of Derivative Security: 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
Restricted Stock Unit (2)	$0.00	11/1/2021		M			635	(3)	(4)	Common Stock	635	$0.00	5081	D
Restricted Stock Unit (2)	$0.00	11/1/2021		M			1382	(5)	(4)	Common Stock	1382	$0.00	9672	D
Restricted Stock Unit (2)	$0.00	11/1/2021		M			514	(6)	(4)	Common Stock	514	$0.00	2054	D
Restricted Stock Unit (2)(7)	$0.00	11/1/2021		A		4649		(8)	(4)	Common Stock	4649	$0.00	4649	D

Explanation of Responses:
(1)	Shares acquired upon vesting of the August 1, 2019, November 1, 2019 and the November 2, 2020 awards of service-based Restricted Stock Units.
(2)	Each Restricted Stock Unit represents a contingent right to receive one share of F5 Networks, Inc. Common Stock on the vest date.
(3)	This November 2, 2020 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning February 1, 2021.
(4)	If the reporting person continues to serve as an officer of the Company on the vest date, the corresponding number of shares of Common Stock of F5 Networks, Inc. will be issued to the reporting person on the vest date.
(5)	Twenty five percent (25%) of this August 1, 2019 award of service-based Restricted Stock Units vests on August 1, 2020, and the remaining seventy five percent (75%) vests in twelve equal quarterly increments beginning November 1, 2020.
(6)	This November 1, 2019 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning February 1, 2020.
(7)	Concurrent with the award of 4,649 service-based Restricted Stock Units, the Company granted the reporting person additional Restricted Stock Units that vest based on performance targets ("Performance RSUs"). If the performance targets are achieved at 100%, the reporting person will receive 4,649 Performance RSUs over the vesting period; the actual number of Performance RSUs received may be more or less depending on whether and to the extent that performance is greater than or less than targets. The Performance RSUs vests over a three-year period in three equal annual installments. Performance RSUs are not reported in Table II; the underlying shares of Performance RSUs will be reported in Table I if and when the Compensation Committee of the Board of Directors determines that the performance targets have been achieved.
(8)	This November 1, 2021 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning February 1, 2022.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Lin Geng C/O F5 NETWORKS, INC. 801 5TH AVENUE SEATTLE, WA 98104			EVP, Chief Technology Officer

Signatures
/s/ Scot F. Rogers by Power of Attorney		11/3/2021
**Signature of Reporting Person		Date

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