ANSYS (ANSS)

13. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

12. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

During each offering, an eligible employee may purchase shares under the Purchase Plan by authorizing payroll deductions of up to 10% of his cash compensation during the offering period. The maximum number of shares that may be purchased by any participating employee during any offering period is limited to 1,920 shares (as adjusted by the Compensation Committee from time to time). Unless the employee has previously withdrawn from the offering, his accumulated payroll deductions will be used to purchase common stock on the last business day of the period at a price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. Under applicable tax rules, an employee may purchase no more than $25,000 worth of common stock in any calendar year. At September 30, 2006, 441,781 shares of common stock had been issued under the Purchase Plan of which 407,371 were issued as of December 31, 2005. The total estimated fair value of purchase rights outstanding under the Purchase Plan that vested during the three and nine months ended September 30, 2006 was $126,000 and $272,000, respectively.

12. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

During each offering, an eligible employee may purchase shares under the Purchase Plan by authorizing payroll deductions of up to 10% of his cash compensation during the offering period. The maximum number of shares that may be purchased by any participating employee during any offering period is limited to 1,920 shares (as adjusted by the Compensation Committee from time to time). Unless the employee has previously withdrawn from the offering, his accumulated payroll deductions will be used to purchase common stock on the last business day of the period at a price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. Under applicable tax rules, an employee may purchase no more than $25,000 worth of common stock in any calendar year. At June 30, 2006, 423,139 shares of common stock had been issued under the Purchase Plan of which 407,371 were issued as of December 31, 2005. The total estimated fair value of purchase rights outstanding under the Purchase Plan that vested during the three and six months ended June 30, 2006 was $75,000 and $146,000, respectively.

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11. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

During each offering, an eligible employee may purchase shares under the Purchase Plan by authorizing payroll deductions of up to 10% of his cash compensation during the offering period. The maximum number of shares that may be purchased by any participating employee during any offering period is limited to 1,920 shares (as adjusted by the Compensation Committee from time to time). Unless the employee has previously withdrawn from the offering, his accumulated payroll deductions will be used to purchase common stock on the last business day of the period at a price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. Under applicable tax rules, an employee may purchase no more than $25,000 worth of common stock in any calendar year. At March 31, 2006, 423,139 shares of common stock had been issued under the Purchase Plan of which 407,371 were issued as of December 31, 2005. The total estimated fair value of purchase rights outstanding under the Purchase Plan that vested during the three months ended March 31, 2006 was $72,000.

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Table of Contents

12. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

During each offering, an eligible employee may purchase shares under the Purchase Plan by authorizing payroll deductions of up to 10% of his cash compensation during the offering period. The maximum number of shares that may be purchased by any participating employee during any offering period is limited to 1,920 shares (as adjusted by the Compensation Committee from time to time). Unless the employee has previously withdrawn from the offering, his accumulated payroll deductions will be used to purchase common stock on the last business day of the period at a price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. Under applicable tax rules, an employee may purchase no more than $25,000 worth of common stock in any calendar year. At December 31, 2005, 407,371 shares of common stock had been issued under the Purchase Plan of which 372,682 were issued as of December 31, 2004.

EMPLOYEE STOCK PURCHASE PLAN

WHEREAS, the ANSYS, Inc. Employee Stock Purchase Plan (the “Plan”) was previously adopted by the Board of Directors and the stockholders of ANSYS, Inc. (the “Company”) and became effective on the consummation of the Company’s initial public offering in 1996;

WHEREAS, the Plan was adopted by the Board of Directors and the stockholders of the Company as an incentive to assist the Company in attracting and retaining key personnel and to align the interests of the participating employees with those of the Company’s stockholders;

WHEREAS, the Plan is intended to constitute an “employee stock purchase plan” within the meaning of Section 423(b) of the Internal Revenue Code of 1986, as amended, and shall be interpreted in accordance with that intent;

WHEREAS, the Plan provides that the total number of shares of the Company’s common stock, $.01 par value per share (the “Common Stock”), which may be issued pursuant the Plan shall not exceed an aggregate of 210,000 shares of Common Stock;

WHEREAS, the Board of Directors of the Company believes that the number of shares of Common Stock remaining available for issuance under the Plan has become insufficient for the Company’s current and anticipated future needs;

WHEREAS, Paragraph (r) of the Plan provides that the Board of Directors of the Company may amend the Plan at any time, subject to certain conditions set forth therein; and

WHEREAS, the Board of Directors of the Company has determined that it is in the best interests of the Company to amend the Plan to provide that an additional 190,000 shares of Common Stock be made available for issuance under the Plan.

NOW, THEREFORE:

1. Amendment of Plan. The first paragraph of the Plan is hereby amended and restated to provide in its entirety as follows:

The purpose of the ANSYS, Inc. Employee Stock Purchase Plan (“the Plan”) is to provide eligible employees of ANSYS, Inc. (the “Company”) and its subsidiaries with opportunities to purchase shares of the Company’s common stock, par value $.01 per share (the “Common Stock”). Four hundred thousand (400,000) shares of Common Stock in the aggregate have been approved and reserved for this purpose. The Plan is intended to constitute an “employee stock purchase plan” within the meaning of Section 423(b) of the Internal Revenue Code of 1986, as amended (the “Code”), and shall be interpreted in accordance with that intent.

2. Effective Date of Amendment. This First Amendment to the Plan shall become effective upon the date that it is adopted by the Board of Directors of the Company; provided, however, that this First Amendment shall be subject to the approval of the Company’s stockholders in accordance with applicable laws and regulations at an annual or special meeting held within twelve months of such effective date.

IN WITNESS WHEREOF, this First Amendment to the Plan has been adopted by the Board of Directors of the Company this 5th day of February, 2004, and approved by the Company’s stockholders at the Company’s Annual Meeting of Stockholders held on May 6, 2004.

12. Employee Stock Purchase Plan

The Company’s 1996 Employee Stock Purchase Plan (the “Purchase Plan”) was adopted by the Board of Directors on April 19, 1996 and was subsequently approved by the Company’s stockholders. The stockholders approved an amendment to the Company’s Employee Stock Purchase Plan on May 6, 2004 to increase the number of shares available for offerings to 800,000 shares. The Purchase Plan is administered by the Compensation Committee. Offerings under the Purchase Plan commence on each February 1 and August 1, and have a duration of six months. An employee who owns or is deemed to own shares of stock representing in excess of 5% of the combined voting power of all classes of stock of the Company may not participate in the Purchase Plan.

During each offering, an eligible employee may purchase shares under the Purchase Plan by authorizing payroll deductions of up to 10% of his cash compensation during the offering period. The maximum number of shares which may be purchased by any participating employee during any offering period is limited to 1,920 shares (as adjusted by the Compensation Committee from time to time). Unless the employee has previously withdrawn from the offering, his accumulated payroll deductions will be used to purchase common stock on the last business day of the period at a price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. Under applicable tax rules, an employee may purchase no more than $25,000 worth of common stock in any calendar year. At December 31, 2004, 372,682 shares of common stock had been issued under the Purchase Plan of which 341,554 were issued as of December 31, 2003.