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Exhibit 99.1

SEI INVESTMENTS COMPANY 1998 EQUITY COMPENSATION PLAN
(As Amended and Restated, April 8, 2003)

The purpose of the SEI Investments Company 1998 Equity Compensation Plan, as amended and restated April 8, 2003 (the "Plan") is to provide (i) designated employees of SEI Investments Company (the "Company") and its subsidiaries, (ii) certain consultants and advisors who perform services for the Company or its subsidiaries and (iii) non-employee members of the Board of Directors of the Company (the "Board") with the opportunity to receive grants of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock and performance units. The Company believes that the Plan will encourage the participants to contribute materially to the growth of the Company, thereby benefitting the Company's shareholders, and will align the economic interests of the participants with those of the shareholders. For purposes of the Plan, the term subsidiary shall refer to any company (whether a corporation, partnership, joint venture or other entity) in which the Company owns, directly or indirectly, a majority of the shares of capital stock or other equity interest.

1. ADMINISTRATION

(a): Committee. The Plan shall be administered and interpreted by a committee consisting of two or more persons appointed by the Board (the "Committee"), each of whom may, but need not, be an "outside director" as defined under section 162(m) of the Internal Revenue Code of 1986, as amended (the "Code"), and related Treasury regulations and a "non-employee director" as defined under Rule 16b-3 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). However, the Board may ratify or approve (and, in the case of grants to the members of the Committee, shall approve) grants, in which case references to the Committee shall be deemed to include the Board.
(b): Committee Authority. The Committee shall have the sole authority to (i) determine the individuals to whom grants shall be made under the Plan, (ii) determine the type, size and terms of the grants to be made to each such individual, (iii) determine the time when the grants will be made and the duration of any applicable exercise or restriction period, including the criteria for exercisability and the acceleration of exercisability and (iv) deal with any other matters arising under the Plan. Notwithstanding the foregoing, in addition to any other grants made by the Committee to Non-Employee Directors in accordance with the terms of the Plan, Non-Employee Directors shall receive stock option grants pursuant to the provisions of Section 6.
(c): Committee Determinations. The Committee shall have full power and authority to administer and interpret the Plan, to make factual determinations and to adopt or amend such rules, regulations, agreements and instruments for implementing the Plan and for the conduct of its business as it deems necessary or advisable, in its sole discretion. The Committee's interpretations of the Plan and all determinations made by the Committee pursuant to the powers vested in it hereunder shall be conclusive and binding on all persons having any interest in the Plan or in any awards granted hereunder. All powers of the Committee shall be executed in its sole discretion, in the best interest of the Company, not as a fiduciary, and in keeping with the objectives of the Plan and need not be uniform as to similarly situated individuals.

2. GRANTS

Awards under the Plan may consist of grants of stock options as described in Section 5 and Section 6 ("Options"), restricted stock as described in Section 7 ("Restricted Stock"), stock appreciation rights as described in Section 8 ("SARs"), performance units as described in Section 9 ("Performance Units") or a combination of the foregoing (hereinafter collectively referred to as "Grants"). All Grants shall be subject to the terms and conditions set forth herein and to such other

terms and conditions consistent with this Plan as the Committee deems appropriate and as are specified in writing by the Committee to the individual in a grant instrument or an amendment to the grant instrument (the "Grant Instrument"). All Grants shall be made conditional upon the Grantee's (as defined below) acknowledgment, in writing or by acceptance of the Grant, that all decisions and determinations of the Committee shall be final and binding on the Grantee, his or her beneficiaries and any other person having or claiming an interest under such Grant. The Committee shall approve the form and provisions of each Grant Instrument. Grants under a particular Section of the Plan need not be uniform as among the grantees.

3. SHARES SUBJECT TO THE PLAN

(a): Shares Authorized. Subject to the adjustment specified below, the aggregate number of shares of common stock of the Company ("Company Stock") that may be issued or transferred under the Plan is the sum of (i) 19,000,000 shares and (ii) the number of shares of Company Stock reserved for issuance, but not subject to outstanding or previously exercised option grants, as of the Original Effective Date of the Plan, under the Company's Stock Option Plan and 1997 Stock Option Plan, plus any shares of Company Stock that, but for the termination of such plans, would have again become available for grants after the Original Effective Date of this Plan, by reason of the termination, expiration, cancellation, forfeiture or surrender of options previously granted under such plans; provided, however, that the maximum number of shares of Company Stock for which Incentive Stock Options may be granted during the term of the Plan is 19,000,000 shares. The maximum aggregate number of shares of Company Stock that shall be subject to Grants made under the Plan to any individual during any calendar year shall be 200,000 shares. The shares may be authorized but unissued shares of Company Stock or reacquired shares of Company Stock, including shares purchased by the Company on the open market for purposes of the Plan. If and to the extent Options or SARs granted under the Plan terminate, expire, or are canceled, forfeited, exchanged or surrendered without having been exercised or if any shares of Restricted Stock or Performance Units are forfeited, the shares subject to such Grants shall again be available for purposes of the Plan. Any shares of Company Stock delivered to the Company to exercise an Option granted under the Plan, or to satisfy the Company's withholding obligation with respect to any Grant, shall also become available for the issuance of Grants under the Plan.
(b): Adjustments. If there is any change in the number or kind of shares of Company Stock outstanding (i) by reason of a stock dividend, spinoff, recapitalization, stock split, or combination or exchange of shares, (ii) by reason of a merger, reorganization or consolidation, (iii) by reason of a reclassification or change in par value, or (iv) by reason of any other extraordinary or unusual event affecting the outstanding Company Stock as a class without the Company's receipt of consideration, or if the value of outstanding shares of Company Stock is substantially reduced as a result of a spinoff or the Company's payment of an extraordinary dividend or distribution, the maximum number of shares of Company Stock available for Grants, the maximum number of shares of Company Stock that any individual participating in the Plan may be granted in any year, the number of shares covered by outstanding Grants, the kind of shares issued under the Plan, and the price per share or the applicable market value of such Grants may be appropriately adjusted by the Committee to reflect any increase or decrease in the number of, or change in the kind or value of, issued shares of Company Stock to preclude, to the extent practicable, the enlargement or dilution of rights and benefits under such Grants; provided, however, that any fractional shares resulting from such adjustment shall be eliminated. Any adjustments determined by the Committee shall be final, binding and conclusive.

4. ELIGIBILITY FOR PARTICIPATION

(a): Eligible Persons. All employees of the Company and its subsidiaries ("Employees"), including Employees who are officers or members of the Board, and members of the Board who are not Employees ("Non-Employee Directors") shall be eligible to participate in the Plan. Consultants and advisors who perform valuable services to the Company or any of its subsidiaries ("Key Advisors") shall be eligible to participate in the Plan if the Key Advisors render bona fide services and such services are not rendered in connection with the offer or sale of securities in a capital-raising transaction.
(b): Selection of Grantees. The Committee shall select the Employees and Key Advisors to receive Grants and shall determine the number of shares of Company Stock subject to a particular Grant in such manner as the Committee determines; provided, however, that Non-Employee Directors shall receive Grants in accordance with Section 6 hereof, in addition to any other Grants that the Committee determines shall be made in accordance with the terms of the Plan. Employees, Key Advisors and Non-Employee Directors who receive Grants under this Plan shall hereinafter be referred to as "Grantees".

5. GRANTING OF OPTIONS

(a)

Number of Shares. The Committee shall determine the number of shares of Company Stock that will be subject to each Grant of Options under this Section 5 to Employees, Non-Employee Directors and Key Advisors.

(b)

Type of Option and Price.

(i): The Committee may grant Incentive Stock Options that are intended to qualify as "incentive stock options" within the meaning of section 422 of the Code ("Incentive Stock Options") or Options that are not intended to so qualify ("Nonqualified Stock Options") or any combination of Incentive Stock Options and Nonqualified Stock Options, all in accordance with the terms and conditions set forth herein. Incentive Stock Options may be granted only to Employees. Nonqualified Stock Options under this Section 5 may be granted to Employees, Non-Employee Directors and Key Advisors.
(ii): The purchase price (the "Exercise Price") of Company Stock subject to an Option shall be determined by the Committee and shall not be less than the Fair Market Value (as defined below) of a share of Company Stock on the date the Option is granted; provided, however, that an Incentive Stock Option may not be granted to an Employee who, at the time of grant, owns stock possessing more than 10 percent of the total combined voting power of all classes of stock of the Company or any "parent corporation" or "subsidiary corporation" of the Company (within the meaning of sections 424(e) and 424(f) of the Code, respectively), unless the Exercise Price per share is not less than 110% of the Fair Market Value of Company Stock on the date of grant. Notwithstanding the foregoing, the Exercise Price of Company Stock subject to a Nonqualified Stock Option may be less than the Fair Market Value of a share of Company Stock on the date the Option is granted ("Discounted Option"), if the grant thereof is subject to the satisfaction of specified performance goals which may, but need not, be in accordance with Section 10 hereof.
(iii): If the Company Stock is publicly traded, then the Fair Market Value per share shall be determined as follows: (x) if the principal trading market for the Company Stock is a national securities exchange or the Nasdaq National Market, the last reported sale price thereof on the relevant date or (if there were no trades on that date) the latest preceding date upon which a sale was reported, or (y) if the Company Stock is not principally

traded on such exchange or market, the mean between the last reported "bid" and "asked" prices of Company Stock on the relevant date, as reported on Nasdaq or, if not so reported, as reported by the National Daily Quotation Bureau, Inc. or as reported in a customary financial reporting service, as applicable and as the Committee determines. If the Company Stock is not publicly traded or, if publicly traded, is not subject to reported transactions or "bid" or "asked" quotations as set forth above, the Fair Market Value per share shall be as determined by the Committee.

(c)

Option Term. The Committee shall determine the term of each Option. The term of any Option shall not exceed ten years from the date of grant. However, an Incentive Stock Option that is granted to an Employee who, at the time of grant, owns stock possessing more than 10 percent of the total combined voting power of all classes of stock of the Company, or any parent or subsidiary of the Company, may not have a term that exceeds five years from the date of grant.

(d)

Exercisability of Options. Options shall become exercisable in accordance with such terms and conditions, consistent with the Plan, as may be determined by the Committee and specified in the Grant Instrument. The Committee may accelerate the exercisability of any or all outstanding Options at any time for any reason.

(e)

Termination of Employment or Service.

(i): Except as provided below, an Option may only be exercised while the Grantee is employed by, or providing service to, the Company as an Employee, Key Advisor or member of the Board. In the event that a Grantee ceases to be employed by, or provide service to, the Company for any reason other than a "disability", death, or termination for "cause", any Option which is otherwise exercisable by the Grantee shall terminate unless exercised within 90 days after the date on which the Grantee ceases to be employed by, or provide service to, the Company (or within such other period of time as may be specified by the Committee), but in any event no later than the date of expiration of the Option term. Except as otherwise provided by the Committee, any of the Grantee's Options that are not otherwise exercisable as of the date on which the Grantee ceases to be employed by, or provide service to, the Company shall terminate as of such date.
(ii): In the event the Grantee ceases to be employed by, or provide service to, the Company on account of a termination for "cause" by the Company, any Option held by the Grantee shall terminate as of the date the Grantee ceases to be employed by, or provide service to, the Company.
(iii): In the event the Grantee ceases to be employed by, or provide service to, the Company because the Grantee is "disabled", any Option which is otherwise exercisable by the Grantee shall terminate unless exercised within one year after the date on which the Grantee ceases to be employed by, or provide service to, the Company (or within such other period of time as may be specified by the Committee), but in any event no later than the date of expiration of the Option term. Except as otherwise provided by the Committee, any of the Grantee's Options which are not otherwise exercisable as of the date on which the Grantee ceases to be employed by, or provide service to, the Company shall terminate as of such date.
(iv): If the Grantee dies while employed by, or providing service to, the Company or within 90 days after the date on which the Grantee ceases to be employed or provide service on account of a termination specified in Section 5(e)(i) above (or within such other period of time as may be specified by the Committee), any Option that is otherwise exercisable by the Grantee shall terminate unless exercised within one year after the date on which the

Grantee ceases to be employed by, or provide service to, the Company (or within such other period of time as may be specified by the Committee), but in any event no later than the date of expiration of the Option term. Except as otherwise provided by the Committee, any of the Grantee's Options that are not otherwise exercisable as of the date on which the Grantee ceases to be employed by, or provide service to, the Company shall terminate as of such date.

(v)

For purposes of this Section 5(e) and Sections 7, 8 and 9:

(A): The term "Company" shall mean the Company and its subsidiaries.
(B): "Employed by, or provide service to, the Company" shall mean employment or service as an Employee, Key Advisor or member of the Board (so that, for purposes of exercising Options and SARs and satisfying conditions with respect to Restricted Stock and Performance Units, a Grantee shall not be considered to have terminated employment or service until the Grantee ceases to be an Employee, Key Advisor and member of the Board), unless the Committee determines otherwise.
(C): "Disability" shall mean a Grantee's becoming disabled within the meaning of section 22(e)(3) of the Code.
(D): "Cause" shall mean, (i) the Grantee's willful misconduct with respect to the business and affairs of the Company; (ii) the Grantee's gross neglect of duties or failure to act which materially and adversely affects the business or affairs of the Company; (iii) the Grantee's commission of an act involving embezzlement or fraud or conviction for any felony; or the (iv) the Grantee's breach of an employment or consulting agreement with the Company.

(f): Exercise of Options. A Grantee may exercise an Option that has become exercisable, in whole or in part, by delivering a notice of exercise to the Company. The Grantee shall pay the Exercise Price for an Option as specified by the Committee (x) in cash, (y) with the approval of the Committee, by delivering shares of Company Stock owned by the Grantee (including Company Stock acquired in connection with the exercise of an Option, subject to such restrictions as the Committee deems appropriate) and having a Fair Market Value on the date of exercise equal to the Exercise Price or by attestation (on a form prescribed by the Committee) to ownership of shares of Company Stock having a Fair Market Value on the date of exercise equal to the Exercise Price, or (z) by such other method as the Committee may approve, including payment through a broker in accordance with procedures permitted by Regulation T of the Federal Reserve Board. Shares of Company Stock used to exercise an Option shall have been held by the Grantee for the requisite period of time to avoid adverse accounting consequences to the Company with respect to the Option. The Grantee shall pay the Exercise Price and the amount of any withholding tax due (pursuant to Section 11) as specified by the Committee.
(g): Limits on Incentive Stock Options. Each Incentive Stock Option shall provide that, if the aggregate Fair Market Value of the Company Stock on the date of the grant with respect to which Incentive Stock Options are exercisable for the first time by a Grantee during any calendar year, under the Plan or any other stock option plan of the Company or a subsidiary, exceeds $100,000, then such Option, as to the excess, shall be treated as a Nonqualified Stock Option. An Incentive Stock Option shall not be granted to any person who is not an Employee of the Company or a parent corporation or a subsidiary corporation (within the meaning of sections 424(e) and 424(f) of the Code, respectively).

6. FORMULA OPTION GRANTS TO NON-EMPLOYEE DIRECTORS

In addition to any other Grants made by the Committee to a Non-Employee Director, a Non-Employee Director shall be entitled to receive Options under the Plan in accordance with this Section 6.

(a)

Initial Grant. Each Non-Employee Director who first becomes a member of the Board of Directors of the Company after the Effective Date of this Plan (as specified in Section 21) shall receive a grant of a Nonqualified Stock Option to purchase 8,000 shares of Company Stock on the date as of which he or she first becomes a member of the Board or at such other proximate time as the Committee may determine.

(b)

Annual Grants. Each Non-Employee Director shall receive an annual grant of a Nonqualified Stock Option to purchase 4,000 shares of Company Stock; provided that such Non-Employee Director qualifies as such on the date of grant. The date of grant of each such annual grant shall be December 31, the date of any year end grants to employees under this Plan or such other proximate time as the Committee shall determine. Notwithstanding the foregoing, effective for annual grants made in 1999 and thereafter, the Board, in its sole discretion, may reduce the number of shares of Company Stock subject to annual Nonqualified Stock Option grants made to the Non-Employee Directors, pursuant to this Section 6(b), at anytime prior to the grant.

(c)

Option Price. The option price of the shares of Company Stock subject to an Option granted under this Section 6 shall be equal to the Fair Market Value of the shares of Company Stock on the date of grant.

(d)

Option Term and Exercisability. The term of each Option granted pursuant to this Section 6 shall be ten years. Options granted under this Section 6 shall become exercisable in four equal installments of whole number of shares on the first, second, third and fourth anniversaries of the date of grant, unless otherwise determined by the Committee. No option, or portion thereof, granted under this Section 6 shall vest or become exercisable after the Grantee ceases to provide services to the Company and all Options shall terminate automatically on the earliest to occur of the expiration of the option term (as described above), or one of the following events:

(i): Upon expiration of ten (10) days after notice by the Company pursuant to Section 13(b)(ii) of the sale of all or substantially all of its assets;
(ii): Thirty (30) days after the date the Non-Employee Director ceases to provide services to the Company for any reason other than death or disability; or
(iii): One year after the date the Non-Employee Director ceases to provide services to the Company as a result of death or disability.

(e)

Applicability of Plan Provisions. Except as otherwise provided in this Section 6, options granted to Non-Employee Directors shall be subject to the provisions of this Plan applicable to Options granted to other persons.

(f)

Administration. Except to the extent provided herein, the provisions of this Section 6 are intended to operate automatically and not require administration. To the extent that any administrative determinations are required, any determinations with respect to the provisions of this Section 6 shall be made by the Committee. If at any time there are not sufficient shares of Company Stock available under the Plan to permit a grant as described in this Section 6, the Grant shall be reduced pro rata (to zero, if necessary) so as not to exceed the number of shares then available under the Plan.

7. RESTRICTED STOCK GRANTS

The Committee may issue or transfer shares of Company Stock to an Employee, Non-Employee Director or Key Advisor under a Grant of Restricted Stock, upon such terms as the Committee deems appropriate. The following provisions are applicable to Restricted Stock:

(a): General Requirements. Shares of Company Stock issued or transferred pursuant to Restricted Stock Grants may be issued or transferred for consideration or for no consideration, as determined by the Committee in its sole discretion. The Committee may establish conditions under which restrictions on shares of Restricted Stock shall lapse over a period of time or according to such other criteria as the Committee deems appropriate. The period of time during which the Restricted Stock will remain subject to restrictions will be designated in the Grant Instrument as the "Restriction Period."
(b): Number of Shares. The Committee shall determine the number of shares of Company Stock to be issued or transferred pursuant to a Restricted Stock Grant and the restrictions applicable to such shares.
(c): Requirement of Employment or Service. If the Grantee ceases to be employed by, or provide service to, the Company (as defined in Section 5(e)) during a period designated in the Grant Instrument as the Restriction Period, or if other specified conditions are not met, the Restricted Stock Grant shall terminate as to all shares covered by the Grant as to which the restrictions have not lapsed, and those shares of Company Stock must be immediately returned to the Company. The Committee may, however, provide for complete or partial exceptions to this requirement as it deems appropriate.
(d): Restrictions on Transfer and Legend on Stock Certificate. During the Restriction Period, a Grantee may not sell, assign, transfer, pledge or otherwise dispose of the shares of Restricted Stock except to a Successor Grantee under Section 12(a). Each certificate for a share of Restricted Stock shall contain a legend giving appropriate notice of the restrictions in the Grant. The Grantee shall be entitled to receive a stock certificate or certificates, or have the legend removed from the stock certificate or certificates covering any of the shares subject to restrictions, as applicable, when all restrictions on such shares have lapsed. The Committee may determine, in its sole discretion, that the Company will not issue certificates for shares of Restricted Stock until all restrictions on such shares have lapsed, or that the Company will retain possession of certificates for any shares issued pursuant to a Restricted Stock Grant, until all restrictions on such shares have lapsed.
(e): Right to Vote and to Receive Dividends. Unless the Committee determines otherwise, during the Restriction Period, the Grantee shall have the right to vote shares of Restricted Stock for which certificates have been issued or transferred to the Grantee and to receive any dividends or other distributions paid on such shares, subject to any restrictions deemed appropriate by the Committee.
(f): Lapse of Restrictions. All restrictions imposed on Restricted Stock shall lapse upon the expiration of the applicable Restriction Period and the satisfaction of all conditions imposed by the Committee. The Committee may determine, as to any or all Restricted Stock Grants, that the restrictions shall lapse without regard to any Restriction Period.

8. STOCK APPRECIATION RIGHTS

(a): General Requirements. The Committee may grant stock appreciation rights ("SARs") to an Employee, Non-Employee Director or Key Advisor separately or in tandem with any Option (for all or a portion of the applicable Option). Tandem SARs may be granted either at the time the Option is granted or at any time thereafter while the Option remains outstanding;

provided, however, that, in the case of an Incentive Stock Option, SARs may be granted only at the time of the Grant of the Incentive Stock Option. The Committee shall establish the base amount of the SAR at the time the SAR is granted. Unless the Committee determines otherwise, the base amount of each SAR shall be equal to the per share Exercise Price of the related Option or, if there is no related Option, the Fair Market Value of a share of Company Stock as of the date of Grant of the SAR.

(b): Tandem SARs. In the case of tandem SARs, the number of SARs granted to a Grantee that shall be exercisable during a specified period shall not exceed the number of shares of Company Stock that the Grantee may purchase upon the exercise of the related Option during such period. Upon the exercise of an Option, the SARs relating to the Company Stock covered by such Option shall terminate. Upon the exercise of SARs, the related Option shall terminate to the extent of an equal number of shares of Company Stock.
(c): Exercisability. An SAR shall be exercisable during the period specified by the Committee in the Grant Instrument and shall be subject to such vesting and other restrictions as may be specified in the Grant Instrument. The Committee may accelerate the exercisability of any or all outstanding SARs at any time for any reason. SARs may only be exercised while the Grantee is employed by the Company or during the applicable period after termination of employment as described in Section 5(e). A tandem SAR shall be exercisable only during the period when the Option to which it is related is also exercisable.
(d): Value of SARs. When a Grantee exercises SARs, the Grantee shall receive in settlement of such SARs an amount equal to the value of the stock appreciation for the number of SARs exercised, payable in cash, Company Stock or a combination thereof. The stock appreciation for an SAR is the amount by which the Fair Market Value of the underlying Company Stock on the date of exercise of the SAR exceeds the base amount of the SAR as described in Subsection (a).
(e): Form of Payment. The Committee shall determine whether the appreciation in an SAR shall be paid in the form of cash, shares of Company Stock, or a combination of the two, in such proportion as the Committee deems appropriate. For purposes of calculating the number of shares of Company Stock to be received, shares of Company Stock shall be valued at their Fair Market Value on the date of exercise of the SAR. If shares of Company Stock are to be received upon exercise of an SAR, cash shall be delivered in lieu of any fractional share.

9. PERFORMANCE UNITS

(a): General Requirements. The Committee may grant performance units ("Performance Units") to an Employee or Key Advisor. Each Performance Unit shall represent the right of the Grantee to receive an amount based on the value of the Performance Unit, if performance goals established by the Committee are met. A Performance Unit shall be based on the Fair Market Value of a share of Company Stock or on such other measurement base as the Committee deems appropriate. The Committee shall determine the number of Performance Units to be granted and the requirements applicable to such Units.
(b): Performance Period and Performance Goals. When Performance Units are granted, the Committee shall establish the performance period during which performance shall be measured (the "Performance Period"), performance goals applicable to the Units ("Performance Goals") and such other conditions of the Grant as the Committee deems appropriate. Performance Goals may relate to the financial performance of the Company or its operating units, the performance of Company Stock, individual performance, or such other criteria as the Committee deems appropriate.

(c): Payment with respect to Performance Units. At the end of each Performance Period, the Committee shall determine to what extent the Performance Goals and other conditions of the Performance Units are met and the amount, if any, to be paid with respect to the Performance Units. Payments with respect to Performance Units shall be made in cash, in Company Stock, or in a combination of the two, as determined by the Committee.
(d): Requirement of Employment or Service. If the Grantee ceases to be employed by, or provide service to, the Company (as defined in Section 5(e)) during a Performance Period, or if other conditions established by the Committee are not met, the Grantee's Performance Units shall be forfeited. The Committee may, however, provide for complete or partial exceptions to this requirement as it deems appropriate.

10. QUALIFIED PERFORMANCE-BASED COMPENSATION

(a): Designation as Qualified Performance-Based Compensation. The Committee may determine that Performance Units, Discounted Options or Restricted Stock granted to an Employee shall be considered "qualified performance-based compensation" under section 162(m) of the Code. The provisions of this Section 10 shall apply to Grants of Discounted Options, Performance Units and Restricted Stock that are to be considered "qualified performance-based compensation" under section 162(m) of the Code.
(b): Performance Goals. When Discounted Options, Performance Units or Restricted Stock that are to be considered "qualified performance-based compensation" are granted, the Committee shall establish in writing (i) the objective performance goals that must be met in order for Discounted Options to be granted, restrictions on the Restricted Stock to lapse or amounts to be paid under the Performance Units, (ii) the Performance Period during which the performance goals must be met, (iii) the threshold, target and maximum amounts that may be paid if the performance goals are met, and (iv) any other conditions, including without limitation provisions relating to death, disability, other termination of employment or Change of Control, that the Committee deems appropriate and consistent with the Plan and section 162(m) of the Code. The performance goals may relate to the Employee's business unit or the performance of the Company and its subsidiaries as a whole, or any combination of the foregoing. The Committee shall use objectively determinable performance goals based on one or more of the following criteria: stock price, earnings per share, net earnings, operating earnings, return on assets, shareholder return, return on equity, growth in assets, unit volume, sales, market share, or strategic business criteria consisting of one or more objectives based on meeting specified revenue goals, market penetration goals, geographic business expansion goals, cost targets or goals relating to acquisitions or divestitures.
(c): Establishment of Goals. The Committee shall establish the performance goals in writing either before the beginning of the Performance Period or during a period ending no later than the earlier of (i) 90 days after the beginning of the Performance Period or (ii) the date on which 25% of the Performance Period has been completed, or such other date as may be required or permitted under applicable regulations under section 162(m) of the Code. The performance goals shall satisfy the requirements for "qualified performance-based compensation," including the requirement that the achievement of the goals be substantially uncertain at the time they are established and that the goals be established in such a way that a third party with knowledge of the relevant facts could determine whether and to what extent the performance goals have been met. The Committee shall not have discretion to increase the amount of compensation that is payable upon achievement of the designated performance goals.
(d): Maximum Payment. If Discounted Options, Restricted Stock, or Performance Units measured with respect to the fair market value of Company Stock, are granted, not more than 100,000

shares of Company Stock may be granted to an Employee under Discounted Options, Performance Units or Restricted Stock for any Performance Period. If Performance Units are measured with respect to other criteria, the maximum amount that may be paid to an Employee with respect to a Performance Period is $1,000,000.

(e): Announcement of Grants. The Committee shall certify and announce the results for each Performance Period to all Grantees immediately following the announcement of the Company's financial results for the Performance Period. If and to the extent that the Committee does not certify that the performance goals have been met, the grants of Restricted Stock or Performance Units for the Performance Period shall be forfeited.

11. WITHHOLDING OF TAXES

(a): Required Withholding. All Grants under the Plan shall be subject to applicable federal (including FICA), state and local tax withholding requirements. The Company may require the Grantee or other person receiving shares to pay the Company the amount of any such taxes that the Company is required to withhold with respect to such Grants or the Company may deduct from the amount payable under a Grant or from other wages paid by the Company the amount of any withholding taxes due with respect to such Grants.
(b): Election to Withhold Shares. If the Committee so permits, a Grantee may elect to satisfy the Company's income tax withholding obligation with respect to an Option, SAR, Restricted Stock or Performance Units paid in Company Stock by having shares withheld up to an amount that does not exceed the Grantee's minimum applicable withholding tax rate for federal (including FICA), state and local tax liabilities. The election must be in a form and manner prescribed by the Committee and shall be subject to the prior approval of the Committee.

12. TRANSFERABILITY OF GRANTS

(a): Nontransferability of Grants. Except as provided below, only the Grantee may exercise rights under a Grant during the Grantee's lifetime. A Grantee may not transfer those rights except by will or by the laws of descent and distribution or, with respect to Grants other than Incentive Stock Options, if permitted in any specific case by the Committee, in its sole discretion, pursuant to a domestic relations order (as defined under the Code or Title I of the Employee Retirement Income Security Act of 1974, as amended, or the regulations thereunder). When a Grantee dies, the personal representative or other person entitled to succeed to the rights of the Grantee ("Successor Grantee") may exercise such rights. A Successor Grantee must furnish proof satisfactory to the Company of his or her right to receive the Grant under the Grantee's will or under the applicable laws of descent and distribution.
(b): Transfer of Nonqualified Stock Options. Notwithstanding the foregoing, the Committee may provide, in a Grant Instrument, that a Grantee may transfer Nonqualified Stock Options to family members, one or more trusts for the benefit of family members, one or more partnerships of which family members are the only partners, or other persons or entities, according to such terms as the Committee may determine; provided that the Grantee receives no consideration for the transfer of an Option and the transferred Option shall continue to be subject to the same terms and conditions as were applicable to the Option immediately before the transfer.

13. CHANGE OF CONTROL OF THE COMPANY

As used herein, a "Change of Control" shall be deemed to have occurred if:

(a): Any "person" (as such term is used in sections 13(d) and 14(d) of the Exchange Act), other than Alfred P. West, Jr., becomes a "beneficial owner" (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing 30% or more of the voting power of the then outstanding securities of the Company;
(b): The consummation of (i) a merger or consolidation of the Company with another corporation where the shareholders of the Company, immediately prior to the merger or consolidation, will not beneficially own, immediately after the merger or consolidation, shares entitling such shareholders to 50% or more of all votes to which all shareholders of the surviving corporation would be entitled in the election of directors (without consideration of the rights of any class of stock to elect directors by a separate class vote), (ii) a sale or other disposition of all or substantially all of the assets of the Company, or (iii) a liquidation or dissolution of the Company;
(c): Any person, other than the Company, has commenced a tender offer or exchange offer for 30% or more of the voting power of the then outstanding shares of the Company; or
(d): At least a majority of the Board does not consist of individuals who were elected, or nominated for election, by the directors in office at the time of such election or nomination.

14. CONSEQUENCES OF A CHANGE OF CONTROL

(a): Notice and Acceleration. Upon a Change of Control, unless the Board determines otherwise, (i) the Company shall provide each Grantee with outstanding Grants written notice of such Change of Control, (ii) all outstanding Options and SARs shall automatically accelerate and become fully exercisable, (iii) the restrictions and conditions on all outstanding Restricted Stock shall immediately lapse, and (iv) Grantees holding Performance Units shall receive a payment in settlement of such Performance Units, in an amount determined by the Committee, based on the Grantee's target payment for the Performance Period and the portion of the Performance Period that precedes the Change of Control.
(b): Assumption of Grants. Upon a Change of Control where the Company is not the surviving corporation (or survives only as a subsidiary of another corporation), unless the Board determines otherwise, all outstanding Options and SARs that are not exercised shall be assumed by, or replaced with comparable options or rights by, the surviving corporation.
(c): Other Alternatives. Notwithstanding the foregoing, subject to subsection (d) below, in the event of a Change of Control, the Board may take one or both of the following actions: the Board may (i) require that Grantees surrender their outstanding Options and SARs in exchange for a payment by the Company, in cash or Company Stock as determined by the Board, in an amount equal to the amount by which the then Fair Market Value of the shares of Company Stock subject to the Grantee's unexercised Options and SARs exceeds the Exercise Price of the Options or the base amount of the SARs, as applicable, or (ii) after giving Grantees an opportunity to exercise their outstanding Options and SARs, terminate any or all unexercised Options and SARs at such time as the Board deems appropriate. Such surrender or termination shall take place as of the date of the Change of Control or such other date as the Board may specify.
(d): Board. The Board making the determinations under this Section 14 following a Change of Control must be comprised of the same members as those on the Board immediately before the Change of Control. If the Board members do not meet this requirement, the automatic provisions of Subsections (a) and (b) shall apply, and the Board shall not have discretion to vary them.
(e): Limitations.

(i): Notwithstanding anything in the Plan to the contrary, in the event of a Change of Control, neither the Committee nor the Board shall have the right to take any actions described in the Plan (including without limitation actions described in Subsection (c) above) that would make the Change of Control ineligible for desired tax treatment if, in the absence of such right, the Change of Control would qualify for such treatment and the Company intends to use such treatment with respect to the Change of Control.
(ii): The Committee shall limit the application of Section 14 if it determines that: (i) a Grantee will receive an "excess parachute payment," as defined in section 280G of the Code, that will be subject to an excise tax under section 4999 of the Code, and (ii) the Committee's imposition of limits on the application Section 14 will result in a Grantee receiving a larger amount on an after-tax basis than he would have received had the Committee not imposed such limitations. If the Committee must limit application of Section 14 as a result of the foregoing, it shall do so in manner that (A) maximizes total compensation paid to the Grantee without causing any compensation to be subject to excise tax under section 4999 of the Code, and (B) unless the Committee determines otherwise, restores, in the following order, Options, SARs, Restricted Stock and Performance Units on a share-by-share or unit-by-unit basis, to the terms that applied before the Change of Control.

15. REQUIREMENTS FOR ISSUANCE OR TRANSFER OF SHARES

No Company Stock shall be issued or transferred in connection with any Grant hereunder unless and until all legal requirements applicable to the issuance or transfer of such Company Stock have been complied with to the satisfaction of the Committee. The Committee shall have the right to condition any Grant made to any Grantee hereunder on such Grantee's undertaking in writing to comply with such restrictions on his or her subsequent disposition of such shares of Company Stock as the Committee shall deem necessary or advisable as a result of any applicable law, regulation or official interpretation thereof, and certificates representing such shares may be legended to reflect any such restrictions. Certificates representing shares of Company Stock issued or transferred under the Plan will be subject to such stop-transfer orders and other restrictions as may be required by applicable laws, regulations and interpretations, including any requirement that a legend be placed thereon.

16. AMENDMENT AND TERMINATION OF THE PLAN

(a): Amendment. The Board may amend or terminate the Plan at any time; provided, however, that the Board shall not amend the Plan without shareholder approval if such approval is required in order to meet the requirements for Incentive Stock Options under section 422 of the Code (and the Board has determined that compliance with section 422 of the Code is desirable), or such approval is required in order to exempt compensation under the Plan from the deduction limit under section 162(m) of the Code.
(b): Termination of Plan. The Plan shall terminate on the day immediately preceding the tenth anniversary of its Original Effective Date (as defined below), unless the Plan is terminated earlier by the Board or is extended by the Board with the approval of the shareholders.
(c): Termination and Amendment of Outstanding Grants. A termination or amendment of the Plan that occurs after a Grant is made shall not materially impair the rights of a Grantee unless the Grantee consents or unless the Committee acts under Section 22(b). The termination of the Plan shall not impair the power and authority of the Committee with respect to an outstanding Grant. Whether or not the Plan has terminated, an outstanding Grant may be terminated or amended under Section 22(b) or may be amended by agreement of the Company and the Grantee consistent with the Plan.

(d): Governing Document. The Plan shall be the controlling document. No other statements, representations, explanatory materials or examples, oral or written, may amend the Plan in any manner. The Plan shall be binding upon and enforceable against the Company and its successors and assigns.

17. FUNDING OF THE PLAN

This Plan shall be unfunded. The Company shall not be required to establish any special or separate fund or to make any other segregation of assets to assure the payment of any Grants under this Plan. In no event shall interest be paid or accrued on any Grant, including unpaid installments of Grants.

18. RIGHTS OF PARTICIPANTS

Nothing in this Plan shall entitle any Employee, Key Advisor, Non-Employee Director or other person to any claim or right to be granted a Grant under this Plan. Neither this Plan nor any action taken hereunder shall be construed as giving any individual any rights to be retained by or in the employ of the Company or any other employment rights.

19. NO FRACTIONAL SHARES

No fractional shares of Company Stock shall be issued or delivered pursuant to the Plan or any Grant. The Committee shall determine whether cash, other awards or other property shall be issued or paid in lieu of such fractional shares or whether such fractional shares or any rights thereto shall be forfeited or otherwise eliminated.

20. HEADINGS

Section headings are for reference only. In the event of a conflict between a title and the content of a Section, the content of the Section shall control.

21. EFFECTIVE DATE OF THE PLAN

Subject to approval by the Company's shareholders, this amendment and restatement of the Plan is effective April 8, 2003. The Plan originally became effective on May 21, 1998 (the "Original Effective Date").

22. MISCELLANEOUS

(a): Grants in Connection with Corporate Transactions and Otherwise. Nothing contained in this Plan shall be construed to (i) limit the right of the Committee to make Grants under this Plan in connection with the acquisition, by purchase, lease, merger, consolidation or otherwise, of the business or assets of any corporation, firm or association, including Grants to employees thereof who become Employees of the Company, or for other proper corporate purposes, or (ii) limit the right of the Company to grant stock options or make other awards outside of this Plan. Without limiting the foregoing, the Committee may make a Grant to an employee of another corporation who becomes an Employee by reason of a corporate merger, consolidation, acquisition of stock or property, reorganization or liquidation involving the Company or any of its subsidiaries in substitution for a stock option or restricted stock grant made by such corporation. The terms and conditions of the substitute grants may vary from the terms and conditions required by the Plan and from those of the substituted stock incentives. The Committee shall prescribe the provisions of the substitute grants.

(b): Compliance with Law. The Plan, the exercise of Options and SARs and the obligations of the Company to issue or transfer shares of Company Stock under Grants shall be subject to all applicable laws and to approvals by any governmental or regulatory agency as may be required. With respect to persons subject to section 16 of the Exchange Act, it is the intent of the Company that the Plan and all transactions under the Plan comply with all applicable provisions of Rule 16b-3 or its successors under the Exchange Act. In addition, it is the intent of the Company that the Plan and applicable Grants under the Plan comply with the applicable provisions of section 162(m) of the Code and section 422 of the Code. To the extent that any legal requirement of section 16 of the Exchange Act or section 162(m) or 422 of the Code as set forth in the Plan ceases to be required under section 16 of the Exchange Act or section 162(m) or 422 of the Code, that Plan provision shall cease to apply. The Committee may revoke any Grant if it is contrary to law or modify a Grant to bring it into compliance with any valid and mandatory government regulation. The Committee may also adopt rules regarding the withholding of taxes on payments to Grantees. The Committee may, in its sole discretion, agree to limit its authority under this Section.
(c): No Shareholder Rights. Except as otherwise provided by the Committee, a Grantee or Successor Grantee shall have no rights as a shareholder with respect to any shares of Company Stock covered by a Grant until the shares are issued or transferred to the Grantee or Successor Grantee on the stock transfer records of the Company.
(d): Grantees Subject to Taxation Outside the United States. With respect to Grantees who are subject to taxation in countries other than the United States, the Committee may make Grants on such terms and conditions as the Committee deems appropriate to comply with the laws of applicable countries, and the Committee may create such procedures, addenda and subplans and make such modifications as may be necessary or advisable to comply with such laws.
(e): Governing Law. The validity, construction, interpretation and effect of the Plan and Grant Instruments issued under the Plan shall exclusively be governed by and determined in accordance with the law of the Commonwealth of Pennsylvania.

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Exhibit 99.1

SEI INVESTMENTS COMPANY 1998 EQUITY COMPENSATION PLAN (As Amended and Restated, April 8, 2003)