Ownership Submission
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

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 *
WILLIAMS DENNIS K
  2. Issuer Name and Ticker or Trading Symbol
IDEX CORP /DE/ [IEX]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) __X__ Other (specify below)
E xecutive Chairman
(Last)
(First)
(Middle)
630 DUNDEE ROAD
3. Date of Earliest Transaction (Month/Day/Year)
09/01/2005
(Street)

NORTHBROOK, IL 60062
4. If Amendment, Date 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
(City)
(State)
(Zip)
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 09/01/2005   M(1)   20,000 A $ 18.08 177,677 D  
Common Stock 09/01/2005   S(1)   20,000 D $ 43.4482 157,677 D  
Common Stock 09/02/2005   M(1)   20,000 A $ 18.08 177,677 D  
Common Stock 09/02/2005   S(1)   20,000 D $ 43.4341 157,677 D  

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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 Underlying Securities
(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
Non-Qualifed Stock Option $ 18.08 09/01/2005   M(1)     20,000 04/14/2001 04/14/2010 Common Stock 20,000 $ 18.08 73,000 D  
Non-Qualifed Stock Option $ 18.08 09/02/2005   M(1)     20,000 04/14/2001 04/14/2010 Common Stock 20,000 $ 18.08 53,000 D  
Deferred Comp Units $ 0             05/06/2005 05/06/2005 Common Stock 91,118   91,118 D  
Non-Qualified Stock Option $ 18.97             03/28/2002 03/28/2011 Common Stock 127,500   127,500 D  
Non-Qualified Stock Option $ 25.3             03/26/2002 03/26/2012 Common Stock 127,500   127,500 D  
Non-Qualified Stock Option $ 19.67             03/27/2004 03/27/2013 Common Stock 150,000   150,000 D  
Non-Qualified Stock Option $ 27.33             03/23/2005 03/23/2014 Common Stock 132,000   132,000 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
WILLIAMS DENNIS K
630 DUNDEE ROAD
NORTHBROOK, IL 60062
  X     E xecutive Chairman

Signatures

 By: /s/ Dennis Williams   09/02/2005
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Stock options exercised per filed 10b5-1 trading program.

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