Ownership Submission
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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  GAYNOR MITCHELL L
2. Date of Event Requiring Statement (Month/Day/Year)
08/16/2007
3. Issuer Name and Ticker or Trading Symbol
JUNIPER NETWORKS INC [JNPR]
(Last)
(First)
(Middle)
1194 NORTH MATHILDA AVENUE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP General Counsel & Secretary
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SUNNYVALE, CA 94089
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
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 469
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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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 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) 03/16/2008(1) 03/16/2014 Common Stock 27,500 $ 18.01 D  
Non-Qualified Stock Option (right to buy) 09/17/2005(1) 09/17/2014 Common Stock 90,000 $ 24.14 D  
Non-Qualified Stock Option (right to buy) 02/07/2005(2) 02/20/2014 Common Stock 250,000 $ 25.53 D  
RSU Award 02/08/2008(3) 02/08/2009 Common Stock 19,000 $ 0 D  
RSU Award 02/08/2008(4) 02/08/2010 Common Stock 9,000 $ 0 D  
RSU Award 02/25/2009(4) 02/25/2011 Common Stock 11,000 $ 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
GAYNOR MITCHELL L
1194 NORTH MATHILDA AVENUE
SUNNYVALE, CA 94089
      VP General Counsel & Secretary  

Signatures

Mitchell L. Gaynor 08/16/2007
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Vests as to 25% of the shares subject to the option one year from the grant date and monthly thereafter as to 1/48th of the shares subject to the option.
(2) Vests as to 25% of the shares one year from the applicable vesting commencement date and 1/48th monthly thereafter.
(3) Vests as to 75% of the shares on the two year anniversary of the grant date and 25% on the third anniversary.
(4) Vests as to 50% of the shares on the two year anniversary of the grant date and 25% annually on the third anniversary and fourth anniversary.

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