| UNITED STATESSECURITIES AND EXCHANGE COMMISSION                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Washington, D.C.  20549                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| FORM 10-Q                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| (MARK ONE)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| (x)    Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| For the quarterly period ended June 27, 2009                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| or                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| (  )   Transition Report Pursuant to Section 13 or 15(d) of the Securities and Exchange Act of 1934    (No Fee Required)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Commission File No. 0-12718                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| SUPERTEX, INC.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| (Exact name of Registrant as specified in its Charter)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| California                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 94-2328535 |
| (State or other jurisdiction of incorporation or organization)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | (IRS Employer Identification #) |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| 1235 Bordeaux Drive                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Sunnyvale, California 94089                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| (Address of principal executive offices)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Registrant's Telephone Number, Including Area Code:  (408) 222-8888                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.                                Yes  [X ]                                                                            No  [    ] |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§229.405 of this chapter) during the preceeding 12 months (or for shorter period that the registrant was requiredto submit and post such files).                               Yes  [   ]                                       No  [    ]                                                                                                                                                                                   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Act). Check one.Large accelerated filer [   ] Accelerated filer [ X ] Non-accelerated filer [   ] Smaller Reporting Company[   ]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).Yes  [   ]                                                                                No  [X ]                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |   |
| Class                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | Outstanding at August 3, 2009 |
| Common Stock, no par value                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 12,897,899 |
| Exhibit index is on Page 34                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Total number of pages: 35                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |

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| Table of Contents |                                                                                        | Page No. |
|-------------------|---------------------------------------------------------------------------------------------|----------|
|              | PART I – FINANCIAL INFORMATION                                                        |     |
| Item 1.           | Financial Statements (Unaudited)                                                            |     |
|              | Condensed Consolidated Statements of Income                                                 | 3        |
|              | Condensed Consolidated Balance Sheets                                                       | 4        |
|              | Condensed Consolidated Statements of Cash Flows                                             | 5        |
|              | Notes to Condensed Consolidated Financial Statements                                        | 6        |
| Item 2.           | Management’s Discussion and Analysis of Financial Condition and Results of Operations | 21       |
| Item 3.           | Quantitative and Qualitative Disclosures About Market Risk                                  | 32       |
| Item 4.           | Controls and Procedures                                                                     | 33       |
|              |                                                                                        |     |
|              | PART II – OTHER INFORMATION                                                           |     |
| Item 1.           | Legal Proceedings                                                                           | 33       |
| Item 1A.          | Risk Factors                                                                                | 33       |
| Item 2.           | Unregistered Sales of Equity Securities and Use of Proceeds                                 | 33       |
| Item 3.           | Defaults Upon Senior Securities                                                             | 34       |
| Item 4.           | Submission of Matters to a Vote of Security Holders                                         | 34       |
| Item 5.           | Other Information                                                                           | 34       |
| Item 6.           | Exhibits                                                                                    | 34       |
|              |                                                                                        |     |
| Signature         |                                                                                        | 35       |

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|                                     |   | Three Months Ended |   |
|------------------------------------------|--------|--------------------|--------|
|                                     |   | June 27, 2009      |   |   | June 28, 2008 |   |
| Net sales                                |   | $                  | 13,555 |   |   | $ | 22,751 |   |
| Cost of sales                            |   |               | 6,425  |   |   |   | 10,000 |   |
| Gross profit                             |   |               | 7,130  |   |   |   | 12,751 |   |
| Research and development                 |   |               | 4,005  |   |   |   | 4,037 |   |
| Selling, general and administrative      |   |               | 2,790  |   |   |   | 3,796 |   |
| Total operating expenses                 |   |               | 6,795  |   |   |   | 7,833 |   |
| Income from operations                   |   |               | 335    |   |   |   | 4,918 |   |
| Interest income                          |   |               | 337    |   |   |   | 1,041 |   |
| Other income(expense), net               |   |               | 449    |   |   |   | (66 | ) |
| Income before provision for income taxes |   |               | 1,121  |   |   |   | 5,893 |   |
| Provision for income taxes               |   |               | 216    |   |   |   | 1,453 |   |
| Net income                               |   | $                  | 905    |   |   | $ | 4,440 |   |
|                                     |   |               |   |   |   |   |   |   |
| Net income per share                     |   |               |   |   |   |   |   |   |
| Basic                                    |   | $                  | 0.07   |   |   | $ | 0.35 |   |
| Diluted                                  |   | $                  | 0.07   |   |   | $ | 0.34 |   |
| Shares used in per share computation:    |   |               |   |   |   |   |   |   |
| Basic                                    |   |               | 12,884 |   |   |   | 12,779 |   |
| Diluted                                  |   |               | 12,965 |   |   |   | 12,881 |   |

See accompanying Notes to Unaudited Condensed Consolidated Financial Statements.

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|                                                                                                           |   | June 27, 2009 |    |   | March 28, 2009 |   |
|----------------------------------------------------------------------------------------------------------------|--------|---------------|---------|--------|----------------|--------|
| ASSETS                                                                                                         |   |          |    |   |           |   |
| Current Assets:                                                                                                |   |          |    |   |           |   |
| Cash and cash equivalents                                                                                      |   | $             | 19,353  |   |           | $      | 24,244 |   |
| Short-term investments                                                                                         |   |          | 43,475  |   |           |   | 33,294 |   |
| Trade accounts receivable, net                                                                                 |   |          | 7,499   |   |           |   | 8,115 |   |
| Inventories, net                                                                                               |   |          | 16,645  |   |           |   | 15,700 |   |
| Prepaid expenses and other current assets                                                                      |   |          | 1,946   |   |           |   | 1,654 |   |
| Prepaid income taxes                                                                                           |   |          | 4,588   |   |           |   | 4,588 |   |
| Deferred income taxes                                                                                          |   |          | 7,625   |   |           |   | 7,625 |   |
| Total current assets                                                                                           |   |          | 101,131 |   |           |   | 95,220 |   |
| Long-term investments                                                                                          |   |          | 80,103  |   |           |   | 79,496 |   |
| Property, plant and equipment, net                                                                             |   |          | 7,927   |   |           |   | 8,473 |   |
| Other assets                                                                                                   |   |          | 388     |   |           |   | 389 |   |
| Deferred income taxes                                                                                          |   |          | 5,301   |   |           |   | 6,726 |   |
| Total assets                                                                                                   |   | $             | 194,850 |   |           | $      | 190,304 |   |
|                                                                                                           |   |          |    |   |           |   |   |   |
|                                                                                                           |   |          |    |   |           |   |   |   |
| LIABILITIES AND SHAREHOLDERS’ EQUITY                                                                     |   |          |    |   |           |   |   |   |
| Current Liabilities:                                                                                           |   |          |    |   |           |   |   |   |
| Trade accounts payable                                                                                         |   | $             | 3,423   |   |           | $      | 2,934 |   |
| Accrued salaries and employee benefits                                                                         |   |          | 9,618   |   |           |   | 8,909 |   |
| Other accrued liabilities                                                                                      |   |          | 969     |   |           |   | 888 |   |
| Deferred revenue                                                                                               |   |          | 3,414   |   |           |   | 3,276 |   |
| Income taxes payable                                                                                           |   |          | 527     |   |           |   | 1,882 |   |
| Total current liabilities                                                                                      |   |          | 17,951  |   |           |   | 17,889 |   |
| Income taxes payable, noncurrent                                                                               |   |          | 4,951   |   |           |   | 4,839 |   |
| Total liabilities                                                                                              |   |          | 22,902  |   |           |   | 22,728 |   |
|                                                                                                           |   |          |    |   |           |   |   |   |
| Commitments and contingencies (Note 9)                                                                         |   |          |    |   |           |   |   |   |
|                                                                                                           |   |          |    |   |           |   |   |   |
| Shareholders’ equity:                                                                                    |   |          |    |   |           |   |   |   |
| Preferred stock, no par value -- 10,000 shares authorized, none outstanding                                    |   |          | -       |   |           |   | - |   |
| Common stock, no par value -- 30,000 shares authorized; issued and outstanding 12,893 shares and 12,872 shares |   |          | 60,749  |   |           |   | 59,549 |   |
| Accumulated other comprehensive loss                                                                           |   |          | (3,227  | )      |           |   | (5,494 | ) |
| Retained earnings                                                                                              |   |          | 114,426 |   |           |   | 113,521 |   |
| Total shareholders' equity                                                                                     |   |          | 171,948 |   |           |   | 167,576 |   |
| Total liabilities and shareholders' equity                                                                     |   | $             | 194,850 |   |           | $      | 190,304 |   |

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|                                                                                         |   | Three Months Ended |    |
|----------------------------------------------------------------------------------------------|--------|--------------------|---------|
|                                                                                         |   | June 27, 2009      |    |   | June 28, 2008 |   |
| CASH FLOWS FROM OPERATING ACTIVITIES                                                         |   |               |    |   |   |   |
| Net income                                                                                   |   | $                  | 905     |   |   | $ | 4,440 |   |
| Non-cash adjustments to net income:                                                          |   |               |    |   |   |   |   |   |
| Depreciation and amortization                                                                |   |               | 665     |   |   |   | 776 |   |
| Provision for doubtful accounts and sales returns                                            |   |               | 5       |   |   |   | 270 |   |
| Provision for excess and obsolete inventories                                                |   |               | 1,542   |   |   |   | 530 |   |
| Deferred income taxes                                                                        |   |               | (20     | ) |   |   | 71 |   |
| Stock-based compensation                                                                     |   |               | 820     |   |   |   | 668 |   |
| Tax benefit related to stock-based compensation plans                                        |   |               | 20      |   |   |   | 162 |   |
| Excess tax benefit related to stock-based compensation                                       |   |               | (4      | ) |   |   | (49 | ) |
| Unrealized (gain) loss from short-term investments, categorized as trading                   |   |               | (455    | ) |   |   | 72 |   |
| (Gain) loss on disposal of property, plant and equipment                                     |   |               | 4       |   |   |   | - |   |
| Changes in operating assets and liabilities:                                                 |   |               |    |   |   |   |   |   |
| Trade accounts receivable                                                                    |   |               | 593     |   |   |   | (773 | ) |
| Inventories                                                                                  |   |               | (2,487  | ) |   |   | 81 |   |
| Prepaid expenses and other assets                                                            |   |               | (273    | ) |   |   | 1,670 |   |
| Trade accounts payable and accrued expenses                                                  |   |               | 1,261   |   |   |   | (467 | ) |
| Deferred revenue                                                                             |   |               | 138     |   |   |   | 243 |   |
| Income taxes payable                                                                         |   |               | (1,243  | ) |   |   | 232 |   |
| Net cash provided by operating activities                                                    |   |               | 1,471   |   |   |   | 7,926 |   |
| CASH FLOWS FROM INVESTING ACTIVITIES                                                         |   |               |    |   |   |   |   |   |
| Purchases of property, plant and equipment, net                                              |   |               | (105    | ) |   |   | (487 | ) |
| Purchases of investments                                                                     |   |               | (14,989 | ) |   |   | (224 | ) |
| Sales of investments                                                                         |   |               | 2,818   |   |   |   | - |   |
| Maturities of investments                                                                    |   |               | 5,550   |   |   |   | - |   |
| Net cash used in investing activities                                                        |   |               | (6,726  | ) |   |   | (711 | ) |
| CASH FLOWS FROM FINANCING ACTIVITIES                                                         |   |               |    |   |   |   |   |   |
| Proceeds from exercise of stock options and employee stock purchase plan                     |   |               | 360     |   |   |   | 1,059 |   |
| Excess tax benefit related to stock-based compensation                                       |   |               | 4       |   |   |   | 49 |   |
| Net cash provided by financing activities                                                    |   |               | 364     |   |   |   | 1,108 |   |
| NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS                                         |   |               | (4,891  | ) |   |   | 8,323 |   |
|                                                                                         |   |               |    |   |   |   |   |   |
| CASH AND CASH EQUIVALENTS:                                                                   |   |               |    |   |   |   |   |   |
| Beginning of period                                                                          |   |               | 24,244  |   |   |   | 17,902 |   |
| End of period                                                                                |   | $                  | 19,353  |   |   | $ | 26,225 |   |
|                                                                                         |   |               |    |   |   |   |   |   |
| Supplemental cash flow disclosures:                                                          |   |               |    |   |   |   |   |   |
| Income taxes paid, net of refunds                                                            |   | $                  | 1,989   |   |   | $ | 683 |   |
|                                                                                         |   |               |    |   |   |   |   |   |
| Supplemental disclosure of non-cash activities:                                              |   |               |    |   |   |   |   |   |
| Additions to property, plant and equipment included in accounts payable and accrued expenses |   | $                  | 18      |   |   | $ | 83 |   |

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|                                                                    |   | June 27, 2009 |   |
|-------------------------------------------------------------------------|--------|---------------|--------|
|                                                                    |   | Level 1       |   |   | Level 2 |   |   | Level 3 |   |   | Total |   |
| Assets:                                                                 |   |          |   |   |   |   |   |   |   |   |   |   |
| Money market funds                                                      |   | $             | -      |   |   | $ | 12,500 |  (1) |   | $ | - |   |   | $ | 12,500 |   |
| Municipal bonds                                                         |   |          |   |   |   |   | 32,927 |  (2) |   |   |   |   |   |   | 32,927 |   |
| Corporate bonds                                                         |   |          |   |   |   |   | 5,777 |  (3) |   |   |   |   |   |   | 5,777 |   |
| Equity mutual funds related to non-qualified deferred compensation plan |   |          | 6,060  |   |   |   | - |   |   |   | - |   |   |   | 6,060 |   |
| Long-term investments in ARS                                            |   |          | -      |   |   |   | - |   |   |   | 80,103 |   |   |   | 80,103 |   |
| Total assets at fair value                                              |   | $             | 6,060  |   |   | $ | 51,204 |   |   | $ | 80,103 |   |   | $ | 137,367 |   |
|                                                                    |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Liabilities:                                                            |   |          |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Obligation related to non-qualified deferred compensation plan          |   | $             | 6,060  |   |   | $ | - |   |   | $ | - |   |   | $ | 6,060 |   |

|                                                                    |   | March 28, 2009 |   |
|-------------------------------------------------------------------------|--------|----------------|--------|
|                                                                    |   | Level 1        |   |   | Level 2 |   |   | Level 3 |   |   | Total |   |
| Assets:                                                                 |   |           |   |   |   |   |   |   |   |   |   |   |
| Money market funds                                                      |   | $              | -      |   |   | $ | 18,382 |  (1) |   | $ | - |   |   | $ | 18,382 |   |
| Municipal bonds                                                         |   |           |   |   |   |   | 21,077 |  (2) |   |   |   |   |   |   | 21,077 |   |
| Variable rate demand notes                                              |   |           |   |   |   |   | 1,000 |   |   |   |   |   |   |   | 1,000 |   |
| Corporate bonds                                                         |   |           |   |   |   |   | 6,557 |  (3) |   |   |   |   |   |   | 6,557 |   |
| Commercial paper                                                        |   |           |   |   |   |   | 992 |   |   |   |   |   |   |   | 992 |   |
| Equity mutual funds related to non-qualified deferred compensation plan |   |           | 5,513  |   |   |   | - |   |   |   | - |   |   |   | 5,513 |   |
| Short-term investments in ARS                                           |   |           | -      |   |   |   | 50 |   |   |   | - |   |   |   | 50 |   |
| Long-term investments in ARS                                            |   |           | -      |   |   |   | - |   |   |   | 79,496 |   |   |   | 79,496 |   |
| Total assets at fair value                                              |   | $              | 5,513  |   |   | $ | 48,058 |   |   | $ | 79,496 |   |   | $ | 133,067 |   |
|                                                                    |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Liabilities:                                                            |   |           |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Obligation related to non-qualified deferred compensation plan          |   | $              | 5,513  |   |   | $ | - |   |   | $ | - |   |   | $ | 5,513 |   |

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| Fair value measurements of assets using level 3 inputs             |   | Long-term investments in ARS |   |
|--------------------------------------------------------------------|--------|------------------------------|--------|
| Beginning balance at March 28, 2009                                |   | $                            | 79,496 |   |
| Redemption of investments in ARS                                   |   |                         | (3,000 | ) |
| Unrealized gain recorded in "Accumulated other comprehensive loss" |   |                         | 3,607  |   |
| Ending balance at June 27, 2009                                    |   | $                            | 80,103 |   |

|                            |   | June 27, 2009 |   |   | March 28, 2009 |   |
|---------------------------------|--------|---------------|--------|--------|----------------|--------|
| Cash                            |   | $             | 5,564  |   |           | $      | 3,967 |   |
| Cash equivalents:               |   |          |   |   |           |   |   |   |
| Money market funds              |   |          | 12,500 |   |           |   | 18,382 |   |
| Municipal bonds                 |   |          | 1,289  |   |           |   | 1,635 |   |
| Corporate bonds                 |   |          | -      |   |           |   | 260 |   |
| Total cash and cash equivalents |   | $             | 19,353 |   |           | $      | 24,244 |   |

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|                                       |   | June 27, 2009  |   |   | March 28, 2009  |   |
|--------------------------------------------|--------|----------------|--------|--------|-----------------|--------|
|                                       |   | Amortized Cost |   |   | Unrealized Gain |   |   | Unrealized Loss |   |   | Carrying Value |   |   | Amortized Cost |   |   | Unrealized Gain |   |   | Unrealized Loss |   |   | Carrying Value |   |
| Short-term investments:                    |   |           |   |   |            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Trading securities                         |   | $              | 6,060  |   |            | $      | - |   |   | $ | - |   |   | $ | 6,060 |   |   | $ | 5,513 |   |   | $ | - |   |   | $ | - |   |   | $ | 5,513 |   |
| Available-for-sale securities:             |   |           |   |   |            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Auction rate securities                    |   |           | -      |   |            |   | - |   |   |   | - |   |   |   | - |   |   |   | 50 |   |   |   | - |   |   |   | - |   |   |   | 50 |   |
| Municipal bonds                            |   |           | 31,630 |   |            |   | 19 |   |   |   | (11 | ) |   |   | 31,638 |   |   |   | 19,438 |   |   |   | 4 |   |   |   | - |   |   |   | 19,442 |   |
| Variable rate demand notes                 |   |           | -      |   |            |   | - |   |   |   | - |   |   |   | - |   |   |   | 1,000 |   |   |   | - |   |   |   | - |   |   |   | 1,000 |   |
| Corporate bonds                            |   |           | 5,770  |   |            |   | 12 |   |   |   | (5 | ) |   |   | 5,777 |   |   |   | 6,393 |   |   |   | - |   |   |   | (96 | ) |   |   | 6,297 |   |
| Commercial paper                           |   |           | -      |   |            |   | - |   |   |   | - |   |   |   | - |   |   |   | 990 |   |   |   | 2 |   |   |   | - |   |   |   | 992 |   |
| Total short-term investments               |   | $              | 43,460 |   |            | $      | 31 |   |   | $ | (16 | ) |   | $ | 43,475 |   |   | $ | 33,384 |   |   | $ | 6 |   |   | $ | (96 | ) |   | $ | 33,294 |   |
|                                       |   |           |   |   |            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Long-term investments:                     |   |           |   |   |            |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Available-for-sale auction rate securities |   | $              | 85,400 |   |            | $      | - |   |   | $ | (5,297 | ) |   | $ | 80,103 |   |   | $ | 88,400 |   |   | $ | - |   |   | $ | (8,904 | ) |   | $ | 79,496 |   |

|                                             |   | June 27, 2009 |   |   | March 28, 2009 |   |
|--------------------------------------------------|--------|---------------|--------|--------|----------------|--------|
| Short-term investment:                           |   |          |   |   |           |   |
| Trading securities:                              |   |          |   |   |           |   |
| Due in one year or less                          |   | $             | 6,060  |   |           | $      | 5,513 |   |
| Available-for-sale securities:                   |   |          |   |   |           |   |   |   |
| Due in one year or less                          |   |          | 37,415 |   |           |   | 26,731 |   |
| Due after ten years                              |   |          | -      |   |           |   | 1,050 |   |
| Total short-term investments                     |   | $             | 43,475 |   |           | $      | 33,294 |   |
|                                             |   |          |   |   |           |   |   |   |
| Long-term investment:                            |   |          |   |   |           |   |   |   |
| Available-for-sale securities at amortized cost: |   |          |   |   |           |   |   |   |
| Due after ten years                              |   | $             | 80,103 |   |           | $      | 79,496 |   |
| Total long-term investments                      |   | $             | 80,103 |   |           | $      | 79,496 |   |

----

| ·   | the decline in market value is due to unusual general market conditions; |
|--------------------|--------------------------------------------------------------------------|

| ·   | recently, some ARS were redeemed at par value; |
|--------------------|------------------------------------------------|

| ·   | these investments are of high credit quality and a significant portion of them are collateralized and are guaranteed by the U.S. Department of Education; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | there have been no defaults on the ARS the Company held as of June 27, 2009; |
|--------------------|----------------------------------------------------------------------------------------|

| ·   | their AAA or Aaa credit ratings have not been reduced as of June 27, 2009; |
|--------------------|----------------------------------------------------------------------------|

| ·   | the Company has no intention to sell the securities below par value and it is not more likely than not that the Company will be required to sell the securities until their value returns to par; and |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the Company received partial redemptions of $12,150,000 at par value in fiscal 2009. Additionally, the Company received payments for partial redemptions of $50,000, $350,000 and $2,650,000 on three ARS holdings in fiscal 2010, all of which at par value. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                                              |   | June 27, 2009 |   |   | March 28, 2009 |   |
|---------------------------------------------------|--------|---------------|--------|--------|----------------|--------|
| Raw materials                                     |   | $             | 1,172  |   |           | $      | 1,128 |   |
| Work-in-process                                   |   |          | 10,869 |   |           |   | 10,449 |   |
| Finished goods                                    |   |          | 2,805  |   |           |   | 2,470 |   |
| Finished goods at distributors and on consignment |   |          | 1,799  |   |           |   | 1,653 |   |
| Total Inventories                                 |   | $             | 16,645 |   |           | $      | 15,700 |   |

|                                                 |   | Three Months Ended |   |
|------------------------------------------------------|--------|--------------------|--------|
|                                                 |   | June 27, 2009      |   |   | June 28, 2008 |   |
| Net income                                           |   | $                  | 905    |   |   | $ | 4,440 |   |
| Unrealized gain on available-for-sale investments(1) |   |               | 2,267  |   |   |   | 451 |   |
| Comprehensive income                                 |   | $                  | 3,172  |   |   | $ | 4,891 |   |

| (1)   | The Unrealized gain of $451,000 for the first quarter of fiscal 2009  is presented on a pre-tax basis. The Company discovered this error in the third quarter of fiscal 2009 and corrected the error by reducing deferred income taxes of $176,000 which was the amount of the error made in the first quarter of fiscal 2009. For thefirst quarter of fiscal 2010, the unrealized gain of $2,267,000 was net of deferred income taxes of $1,445,000. |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                    |   |                |    |   | Options Outstanding |   |
|-------------------------|--------|---------------------|---------|--------|---------------------|--------|
|                    |   | Available for Grant |    |   | Number of Shares    |   |   | Weighted Average Exercise Price |   |
| Balance, March 28, 2009 |   |                | 160,109 |   |                |   | 1,467,835 |   |   | $ | 26.94 |   |
| Granted                 |   |                | (5,000  | )      |                |   | 5,000 |   |   |   | 24.49 |   |
| Exercised               |   |                | -       |   |                |   | (18,595 | ) |   |   | 15.49 |   |
| Canceled                |   |                | 2,000   |   |                |   | (2,000 | ) |   |   | 33.95 |   |
| Balance, June 27, 2009  |   |                | 157,109 |   |                |   | 1,452,240 |   |   |   | 27.07 |   |

----

|                     |   |   |               |   | Options Outstanding |                                                |   | Options Exercisable |                            |
|--------------------------|--------|--------|--------------------|--------|---------------------|-----------------------------------------------------|--------|---------------------|---------------------------------|
| Range of Exercise Prices |   |   | Number Outstanding |   |                | Weighted-Average Remaining Contractual Life (Years) |   |                | Weighted-Average Exercise Price |   |   | Number Outstanding |   |   | Weighted-Average Exercise Price |   |
| $                        | 11.30  | -      | $                  | 14.99  |                |                                                |   | 11,500              |                            |   |   | 0.33 |   |   | $ | 12.32 |   |   |   | 11,500 |   |   | $ | 12.32 |   |
|                     | 15.00  | -      |               | 19.99  |                |                                                |   | 234,000             |                            |   |   | 1.91 |   |   |   | 17.28 |   |   |   | 200,880 |   |   |   | 17.28 |   |
|                     | 20.00  | -      |               | 24.99  |                |                                                |   | 433,100             |                            |   |   | 9.08 |   |   |   | 20.93 |   |   |   | 20,420 |   |   |   | 21.44 |   |
|                     | 25.00  | -      |               | 29.99  |                |                                                |   | 234,880             |                            |   |   | 8.59 |   |   |   | 27.15 |   |   |   | 38,740 |   |   |   | 26.57 |   |
|                     | 30.00  | -      |               | 34.99  |                |                                                |   | 270,260             |                            |   |   | 5.38 |   |   |   | 33.76 |   |   |   | 109,685 |   |   |   | 33.71 |   |
|                     | 35.00  | -      |               | 39.99  |                |                                                |   | 104,300             |                            |   |   | 8.00 |   |   |   | 35.84 |   |   |   | 24,860 |   |   |   | 35.82 |   |
|                     | 40.00  | -      |               | 44.99  |                |                                                |   | 146,200             |                            |   |   | 4.36 |   |   |   | 40.90 |   |   |   | 70,500 |   |   |   | 40.87 |   |
|                     | 45.00  | -      |               | 46.92  |                |                                                |   | 18,000              |                            |   |   | 4.43 |   |   |   | 46.92 |   |   |   | 7,200 |   |   |   | 46.92 |   |
| $                        | 11.30  | -      | $                  | 46.92  |                |                                                |   | 1,452,240           |                            |   |   | 6.48 |   |   | $ | 27.07 |   |   |   | 483,785 |   |   | $ | 26.64 |   |

----

----

|                                                  |   | Three Months Ended |   |
|-------------------------------------------------------|--------|--------------------|--------|
|                                                  |   | June 27, 2009      |   |   | June 28, 2008 |   |
| BASIC:                                                |   |               |   |   |   |   |
| Net income                                            |   | $                  | 905    |   |   | $ | 4,440 |   |
| Weighted average shares outstanding for the period    |   |               | 12,884 |   |   |   | 12,779 |   |
| Net income per share                                  |   | $                  | 0.07   |   |   | $ | 0.35 |   |
|                                                  |   |               |   |   |   |   |   |   |
| DILUTED:                                              |   |               |   |   |   |   |   |   |
| Net income                                            |   | $                  | 905    |   |   | $ | 4,440 |   |
| Weighted average shares outstanding for the period    |   |               | 12,884 |   |   |   | 12,779 |   |
| Effect of dilutive securities: stock options and ESPP |   |               | 81     |   |   |   | 102 |   |
| Total                                                 |   |               | 12,965 |   |   |   | 12,881 |   |
| Net income per share                                  |   | $                  | 0.07   |   |   | $ | 0.34 |   |

----

| Description                      |   | Balance at Beginning of Period |   |   | Charge(1) |   |   | Deductions and Other(2) |   |   | Balance at End of Period |   |
|----------------------------------|--------|--------------------------------|--------|--------|-----------|--------|--------|-------------------------|--------|--------|--------------------------|--------|
| Three months ended June 27, 2009 |   |                           |   |   |      |   |   |                    |   |   |                     |   |
| Allowance for sales returns      |   | $                              | 266    |   |      | $      | 25     |                    |   | $      | (78                      | )      |   | $ | 213 |   |
|                             |   |                           |   |   |      |   |   |                    |   |   |                     |   |   |   |   |   |
| Three months ended June 28, 2008 |   |                           |   |   |      |   |   |                    |   |   |                     |   |   |   |   |   |
| Allowance for sales returns      |   | $                              | 483    |   |      | $      | 264    |                    |   | $      | (381                     | )      |   | $ | 366 |   |

----

| Payment Due by Year |   | Operating Lease |   |   | Estimated Sublease Income |   |
|---------------------|--------|-----------------|--------|--------|---------------------------|--------|
| Less than 1 year    |   | $               | 1,110  |   |                      | $      | 6 |   |
| 2 years             |   |            | 866    |   |                      |   | - |   |
| 3 years             |   |            | 11     |   |                      |   | - |   |
|                |   | $               | 1,987  |   |                      | $      | 6 |   |

|                |   | Three Months Ended |   |
|---------------------|--------|--------------------|--------|
| Net Sales           |   | June 27, 2009      |   |   | June 28, 2008 |   |
| Medical Electronics |   | $                  | 5,381  |   |   | $ | 9,528 |   |
| LED Lighting        |   |               | 2,876  |   |   |   | 1,353 |   |
| Imaging             |   |               | 2,638  |   |   |   | 6,307 |   |
| Industrial/Other    |   |               | 1,640  |   |   |   | 2,898 |   |
| Telecom             |   |               | 1,020  |   |   |   | 2,665 |   |
| Net Sales           |   | $                  | 13,555 |   |   | $ | 22,751 |   |

----

|                               |   | Three Months Ended |   |
|------------------------------------|--------|--------------------|--------|
| Net Sales                          |   | June 27, 2009      |   |   | June 28, 2008 |   |
| United States                      |   | $                  | 5,133  |   |   | $ | 7,700 |   |
| China                              |   |               | 4,095  |   |   |   | 4,360 |   |
| Asia (excluding China & Korea) |   |               | 2,412  |   |   |   | 5,021 |   |
| Europe                             |   |               | 1,177  |   |   |   | 3,195 |   |
| Korea                              |   |               | 673    |   |   |   | 2,301 |   |
| Other                              |   |               | 65     |   |   |   | 174 |   |
| Net Sales                          |   | $                  | 13,555 |   |   | $ | 22,751 |   |

|                               |   | June 27, 2009 |   |   | March 28, 2009 |   |
|------------------------------------|--------|---------------|--------|--------|----------------|--------|
| United States                      |   | $             | 6,510  |   |           | $      | 6,952 |   |
| Hong Kong                          |   |          | 1,417  |   |           |   | 1,521 |   |
| Property, plant and equipment, net |   | $             | 7,927  |   |           | $      | 8,473 |   |

----

----

----

|                |   | Three Months Ended |   |
|---------------------|--------|--------------------|--------|
| Net Sales           |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |   | Sequential Change |   |   | Year-Over-Year Change |   |
| Medical Electronics |   | $                  | 5,381  |   |   | $ | 6,401 |   |   | $ | 9,528 |   |   |   | -16 | % |   |   | -44 | % |
| LED Lighting        |   |               | 2,876  |   |   |   | 1,977 |   |   |   | 1,353 |   |   |   | 45 | % |   |   | 113 | % |
| Imaging             |   |               | 2,638  |   |   |   | 3,080 |   |   |   | 6,307 |   |   |   | -14 | % |   |   | -58 | % |
| Industrial/Other    |   |               | 1,640  |   |   |   | 2,394 |   |   |   | 2,898 |   |   |   | -31 | % |   |   | -43 | % |
| Telecom             |   |               | 1,020  |   |   |   | 1,158 |   |   |   | 2,665 |   |   |   | -12 | % |   |   | -62 | % |
| Net Sales           |   | $                  | 13,555 |   |   | $ | 15,010 |   |   | $ | 22,751 |   |   |   | -10 | % |   |   | -40 | % |

|                |   | Three Months Ended |   |
|---------------------|--------|--------------------|--------|
| Net Sales           |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |
| Medical Electronics |   |               | 40     | % |   |   | 43 | % |   |   | 42 | % |
| LED Lighting        |   |               | 21     | % |   |   | 13 | % |   |   | 6 | % |
| Imaging             |   |               | 19     | % |   |   | 20 | % |   |   | 28 | % |
| Industrial/Other    |   |               | 12     | % |   |   | 16 | % |   |   | 13 | % |
| Telecom             |   |               | 8      | % |   |   | 8 | % |   |   | 11 | % |
| Net Sales           |   |               | 100    | % |   |   | 100 | % |   |   | 100 | % |

----

|                               |   | Three Months Ended |   |
|------------------------------------|--------|--------------------|--------|
| Net Sales                          |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |   | Sequential Change |   |   | Year-Over-Year Change |   |
| United States                      |   | $                  | 5,133  |   |   | $ | 6,282 |   |   | $ | 7,700 |   |   |   | -18 | % |   |   | -33 | % |
| China                              |   |               | 4,095  |   |   |   | 4,061 |   |   |   | 4,360 |   |   |   | 1 | % |   |   | -6 | % |
| Asia (excluding China & Korea) |   |               | 2,412  |   |   |   | 2,201 |   |   |   | 5,021 |   |   |   | 10 | % |   |   | -52 | % |
| Europe                             |   |               | 1,177  |   |   |   | 1,797 |   |   |   | 3,195 |   |   |   | -35 | % |   |   | -63 | % |
| Korea                              |   |               | 673    |   |   |   | 604 |   |   |   | 2,301 |   |   |   | 11 | % |   |   | -71 | % |
| Other                              |   |               | 65     |   |   |   | 65 |   |   |   | 174 |   |   |   | 0 | % |   |   | -63 | % |
| Net Sales                          |   | $                  | 13,555 |   |   | $ | 15,010 |   |   | $ | 22,751 |   |   |   | -10 | % |   |   | -40 | % |
|                               |   |               |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| International Sales                |   | $                  | 8,422  |   |   | $ | 8,728 |   |   | $ | 15,051 |   |   |   | -4 | % |   |   | -44 | % |
| Domestic Sales                     |   |               | 5,133  |   |   |   | 6,282 |   |   |   | 7,700 |   |   |   | -18 | % |   |   | -33 | % |
| Net Sales                          |   | $                  | 13,555 |   |   | $ | 15,010 |   |   | $ | 22,751 |   |   |   | -10 | % |   |   | -40 | % |

----

|                                                                     |   | Three Months Ended |   |
|--------------------------------------------------------------------------|--------|--------------------|--------|
| (Dollars in thousands)                                                   |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |
| Gross Margin Percentage                                                  |   |               | 53     | % |   |   | 42 | % |   |   | 56 | % |
| Included in Gross Margin Percentage Above                                |   |               |   |   |   |   |   |   |   |   |   |   |
| Gross Margin Benefit from Cost of Previously Written Down Inventory Sold |   | $                  | 287    |   |   | $ | 247 |   |   | $ | 326 |   |
| Percentage of Net Sales                                                  |   |               | 2      | % |   |   | 2 | % |   |   | 1 | % |

|                    |   | Three Months Ended |   |
|-------------------------|--------|--------------------|--------|
| (Dollars in thousands)  |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |   | Sequential Change |   |   | Year-Over-Year Change |   |
| R&D Expenses        |   | $                  | 4,005  |   |   | $ | 3,247 |   |   | $ | 4,037 |   |   |   | 23 | % |   |   | -1 | % |
| Percentage of Net Sales |   |               | 30     | % |   |   | 22 | % |   |   | 18 | % |   |   |   |   |   |   |   |   |

----

|                    |   | Three Months Ended |   |
|-------------------------|--------|--------------------|--------|
| (Dollars in thousands)  |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |   | Sequential Change |   |   | Year-Over-Year Change |   |
| SG&A Expenses       |   | $                  | 2,790  |   |   | $ | 2,479 |   |   | $ | 3,796 |   |   |   | 13 | % |   |   | -27 | % |
| Percentage of Net Sales |   |               | 21     | % |   |   | 17 | % |   |   | 17 | % |   |   |   |   |   |   |   |   |

|                                        |   | Three Months Ended |   |
|---------------------------------------------|--------|--------------------|--------|
| (Dollars in thousands)                      |   | June 27, 2009      |   |   | March 28, 2009 |   |   | June 28, 2008 |   |   | Sequential Change |   |   | Year-Over-Year Change |   |
| Interest Income                             |   | $                  | 337    |   |   | $ | 446 |   |   | $ | 1,041 |   |   |   | -24 | % |   |   | -68 | % |
| Other Income (Expense), Net                 |   |               | 449    |   |   | $ | (219 | ) |   | $ | (66 | ) |   |   | -305 | % |   |   | -780 | % |
| Total Interest Income and Other Income, Net |   | $                  | 786    |   |   | $ | 227 |   |   | $ | 975 |   |   |   | 246 | % |   |   | -19 | % |
| Percentage of Net Sales                     |   |               | 6      | % |   |   | 2 | % |   |   | 4 | % |   |   |   |   |   |   |   |   |

----

----

|                                                 |   | Three Months Ended |   |
|------------------------------------------------------|--------|--------------------|--------|
| (Dollars in thousands)                               |   | June 27, 2009      |   |   | June 28, 2008 |   |
| Net cash provided by operating activities            |   | $                  | 1,471  |   |   | $ | 7,926 |   |
| Net cash used in investing activities                |   |               | (6,726 | ) |   |   | (711 | ) |
| Net cash provided by financing activities            |   |               | 364    |   |   |   | 1,108 |   |
| Net increase (decrease) in cash and cash equivalents |   | $                  | (4,891 | ) |   | $ | 8,323 |   |

----

| ·   | the decline in market value is due to unusual general market conditions; |
|--------------------|--------------------------------------------------------------------------|

| ·   | recently, some ARS were redeemed at par value; |
|--------------------|------------------------------------------------|

| ·   | these investments are of high credit quality and a significant portion of them are collateralized and are guaranteed by the U.S. Department of Education; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | there have been no defaults on the ARS we held as of June 27, 2009; |
|--------------------|---------------------------------------------------------------------|

| ·   | their AAA or Aaa credit ratings have not been reduced as of June 27, 2009; |
|--------------------|----------------------------------------------------------------------------|

| ·   | we have no intention to sell the securities below par value and it is not more likely than not that we will be required to sell the securities until their value returns to par; and |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | we received partial redemptions of $12,150,000 at par value in fiscal 2009. Additionally, we received payments for partial redemptions of $50,000, $350,000 and $2,650,000 on three ARS holdings in fiscal 2010, all of which at par value. |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                               |   | Payment Due by Year |   |
|------------------------------------|--------|---------------------|--------|
| Contractual Obligations            |   | Total               |   |   | Less than 1 Year |   |   | 1-2 Years |   |   | 2-3 Years |   |
| Operating lease obligations (1)    |   | $                   | 1,987  |   |   | $ | 1,110 |   |   | $ | 866 |   |   | $ | 11 |   |
| Purchase obligations               |   |                | 4,349  |   |   |   | 3,951 |   |   |   | 138 |   |   |   | 260 |   |
| Total contractual cash obligations |   | $                   | 6,336  |   |   | $ | 5,061 |   |   | $ | 1,004 |   |   | $ | 271 |   |

----

----

----

----

|   Exhibit 31.1 & 31.2 - | Certification of Chief Executive Officer and of Chief Financial Officer pursuant to Securities and Exchange Act Rules 13a-14(a) and 15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. |
|---------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   Exhibit 32.1 & 32.2 -  | Certification of Chief Executive Officer and of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. |
|----------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

|                             |   |   | SUPERTEX, INC.                                      |
|----------------------------------|--------|--------|-----------------------------------------------------|
|                             |   |   | (Registrant)                                        |
|                             |   |   |                                                |
|                             |   |   |                                                |
| Dated:  August 5, 2009 |   |   |                                                |
|                             |   |   | By: /s/PHILLIP A. KAGEL                             |
|                             |   |   | Phillip A. Kagel                                    |
|                             |   |   | Vice President, Finance and Chief Financial Officer |
|                             |   |   | (Principal Financial and Accounting Officer)        |

----