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 *
HEINZE EDWARD J
   2. Issuer Name and Ticker or Trading Symbol
CASTELLE \CA\ [CSTL] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
V.P. Sales, US
(Last)
(First)
(Middle)
855 JARVIS DRIVE, SUITE 100		 3. Date of Earliest Transaction (Month/Day/Year)
05/27/2005
(Street)

MORGAN HILL, CA 95037		 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 05/27/2005   M   1,876 A $ 0.875 4,376 D  
Common Stock 05/27/2005   S   1,876 D $ 2.9608 2,500 D  
Common Stock 05/27/2005   M   2,292 A $ 0.68 4,792 D  
Common Stock 05/27/2005   S   2,292 D $ 2.9608 2,500 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
Option (Right To Buy) $ 0.875 05/27/2005 05/27/2005 M     1,980 11/08/2001(1) 11/08/2007 Common Stock 1,980 $ 0.875 0 D  
Option (Right To Buy) $ 0.68 05/27/2005 05/27/2005 M     2,292 04/11/2002(2) 04/11/2008 Common Stock 2,292 $ 0.68 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
HEINZE EDWARD J
855 JARVIS DRIVE
SUITE 100
MORGAN HILL, CA 95037		       V.P. Sales, US  

Signatures

 /s/ Edward J Heinze   05/27/2005
**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) Options granted pursuant to Issuer's 1988 Equity Incentive Plan. Tewnty-Five percent (25%) of the options shall vest on November 8, 2001, and the remaining options shall vest in 36 equal monthly installments thereafter.
(2) Options granted pursuant to the Issuer's 1988 Equity Incentive Plan. Twenty-Five percent (25%) of the options shall vest on April 11, 2002, and the remaining options shall vest in 36 equal monthly installments thereafter.

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