SEC FORM 4

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Tsang Michael

(Last)

(First)

(Middle)

1235 BORDEAUX DR.

(Street)

SUNNYVALE

94089

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
SUPERTEX INC [ supx ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	VP, Standard Products

3. Date of Earliest Transaction (Month/Day/Year)
05/26/2009

4. If Amendment, Date of 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

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
common stock	05/26/2009		M		1,500	A	$11.3	1,500	D
common stock	05/26/2009		S		400	D	$24.42	1,100	D
common stock	05/26/2009		S		600	D	$24.27	500	D
common stock	05/26/2009		S		100	D	$24.26	400	D
common stock	05/26/2009		S		100	D	$24.4201	300	D
common stock	05/26/2009		S		100	D	$24.33	200	D
common stock	05/26/2009		S		200	D	$24.4	0	D

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 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: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
ISO stock options (to exercise common stock)	$11.3	05/26/2009		M			1,500	09/03/2007	09/03/2009	common stock	1,500	$11.3	64,000⁽¹⁾⁽²⁾⁽³⁾⁽⁴⁾⁽⁵⁾⁽⁶⁾⁽⁷⁾	D

Explanation of Responses:

1. ISO Option (to exercise common stock). Exercise price: $17.34. Shares granted: 5,000. Shares exercised: 3,000. Shares exercisable: 2,000. Expiration date: 12/1/2010. Held Direct.

2. ISO Option (to exercise common stock). Exercise price: $15.67. Shares granted: 5,000. Shares exercised: 3,000. Shares exercisable: 1,000. 1,000 shares exercisable 6/1/2009. Expiration date: 6/1/2011. Held Direct.

3. ISO Option (to exercise common stock). Exercise price: $17.39. Shares granted: 5,000. Shares exercisable: 3,000. 1,000 shares exercisable 6/1/2009. 1,000 shares exercisable 6/1/2010. Expiration date: 6/1/2012. Held Direct.

4. ISO Option (to exercise common stock). Exercise Price: $33.6700. Shares granted: 9,500. Shares Exercisable: 4,200. 2,400 shares exercisable on 3/1/2010. 2,900 shares exercisable on 3/1/2011. Expiration Date: 3/1/2013. Held Direct.

5. NQ Option (to exercise common stock). Exercise Price: $33.6700. Shares granted: 5,500. Shares Exercisable: 1,525. 1,500 shares exercisable on 3/1/2010. 2,475 shares exercisable on 3/1/2011. Expiration Date: 3/1/2013. Held Direct.

6. NQ Option (to exercise common stock). Exercise Price: $33.9500. Shares granted: 5,000. Shares Exercisable: 1,000. 1,000 shares exercisable on 12/3/2009. 1,000 shares exercisable on 12/3/2010. 1,000 shares exercisable on 12/3/2011. 1,000 shares exercisable on 12/3/2012. Expiration Date: 12/3/2017. Held Direct.

7. NQ Option (to exercise common stock). Exercise Price: $20.8500. Shares Granted: 35,000. Shares Exercisable: 0. 7,000 shares exercisable on 12/01/2009. 7,000 shares exercisable on 12/01/2010. 7,000 shares exercisable on 12/01/2011. 7,000 shares exercisable on 12/01/2012. 7,000 shares exercisable on 12/01/2013. Expiration Date: 12/01/2018. Held Direct.

	Michael Tsang	05/27/2009
	** 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 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).
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