AMENDMENT NUMBER TWO TO THE NICHOLS RESEARCH CORPORATION 1988 EMPLOYEES' STOCK PURCHASE PLAN Pursuant to Section 7.1 of the Nichols Research Corporation 1988 Employees' Stock Purchase Plan (the "Plan"), Nichols Research Corporation (the "Employer"), hereby amends the Plan as follows: 1. Effective December 1, 1989, the first sentence of Section 3.1 is hereby deleted in its entirety and the following new sentence is substituted in its place: On March 1, 1989, and each March 1, June 1, September 1, and December 1 thereafter, an Employee may elect to participate in the Plan by authorizing payroll deductions under Section 5.1. 2. Effective December 1, 1989, the third sentence of Section 5.1 is deleted in its entirety and the following new sentence is substituted in its place: Deductions may be authorized beginning March 1, 1989, or any June 1, September 1, December 1, or March 1 thereafter, in any integral percentage, up to ten (10%) percent of an Employee's basic rate of compensation paid by the Employer. Except as amended above, the Plan shall remain in full force and effect according to its terms and provisions. NICHOLS RESEARCH CORPORATION Chris H. Horgen By:_________________________ Chris H. Horgen Chief Executive Officer AMENDMENT THREE 1988 EMPLOYEE STOCK PURCHASE PLAN The Nichols Research Corporation 1988 Employee Stock Purchase Plan is hereby amended to provide that notwithstanding anything to the contrary, the Plan shall be administered by a committee of not less than two members and that all committee members shall be disinterested directors as that term is defined under Rule 16(b-3) as adopted by the Securities and Exchange Commission. This Amendment shall be effective May 1, 1991. In addition, the Plan is further amended to provide that all persons subject to the reporting requirements of Section 16(a) of the Securities Exchange Act of 1934, who ceases participation in the Plan may not participate again for at least six (6) months. In all other respects, the Plan as previously amended, shall remain in full force and effect according to its terms and conditions. NICHOLS RESEARCH CORPORATION Chris H. Horgen By:________________________________ Chris H. Horgen Its Chief Executive Officer AMENDMENT NUMBER FOUR TO THE NICHOLS RESEARCH CORPORATION 1988 EMPLOYEES' STOCK PURCHASE PLAN Pursuant to Section 7.1 of the Nichols Research Corporation 1988 Employees' Stock Purchase Plan (the "Plan"), Nichols Research Corporation (the "Employer"), hereby amends the Plan as follows: 1. Effective March 1, 1992, the last sentence of Section 3.1 of the Plan is hereby deleted in its entirety and the following new sentence is substituted in its place: Once participation is discontinued hereunder, an Employee may not again elect to participate in the Plan until the next succeeding March or, in the case of an Employee subject to the reporting requirements of Section 16(a) of the Securities Act of 1934, until the later of (I) the March 1 immediately following his discontinuance of payroll deductions, or (ii) the March 1 next occurring after the date which is six (6) months after the date such Employee discontinued payroll deductions under the Plan. 2. Effective March 1, 1992, the last sentence of Section 5.1 of the the Plan is hereby deleted in its entirety and the following new sentence is substituted in its place: A payroll deduction authorization hereunder shall remain in effect until changed or discontinued under Section 5.3. 3. Effective March 1, 1992, Section 5.3 of the Plan is hereby deleted in its entirety and the following new Section 5.3 is substituted in its place: 5.3 CHANGE; DISCONTINUANCE. (a) Any Employee who is not subject to the reporting requirements of Section 16(a) of the Securities Exchange Act of 1934 may decrease (but not below 1% of his basic rate of compensation paid by the Employer) or increase (within the limits specified in Section 5.1) payroll deductions authorized under Section 5.1 by signing and filing with his Employer a form provided for this purpose. Such change in payroll deductions shall be effective on the March 1, June 1, September 1, or December 1 next occurring after the Employee's change form is received by his Employer. An Employee subject to the reporting requirements of Section 16(a) of the Securities Exchange Act of 1934 may not change his payroll deductions in accordance with this Section 5.3 (b) An Employee may discontinue payroll deductions authorized under Section 5.1 at any time, by signing and filing with his Employer, within the time prescribed in rules and regulations adopted under Article VIII, a form provided for this purpose. Once discontinued hereunder, payroll deductions may not be made again until the next succeeding March 1 or, in the case of an Employee subject to the reporting requirements of Section 16(a) of the Securities Exchange Act of 1934, until the later of (I) the March 1 immediately following his discontinuance of payroll deductions, or (ii) the March 1 next occurring after the date which is six (6) months after the date such Employee discontinued payroll deductions under the Plan. Except as amended above, the Plan shall remain in full force and effect according to its terms and provisions. Done this the 8th day of April, 1993. NICHOLS RESEARCH CORPORATION Chris H. Horgen By:______________________________ Its Chief Executive Officer AMENDMENT NUMBER FIVE TO THE NICHOLS RESEARCH CORPORATION 1988 EMPLOYEES' STOCK PURCHASE PLAN Pursuant to Section 7.1 of the Nichols Research Corporation 1988 Employees' Stock Purchase Plan (the "Plan"), Nichols Research Corporation (the "Company"), hereby amends the Plan as follows: 1. Subject to approval by the shareholders of the Company, effective March 1, 1994, the first sentence of Section 4.2 of the Plan is hereby deleted in its entirety and the following new sentence is substituted in its place: Stock shall be purchased under each Option at 85% of its fair market value on the last day of the Option Period. 2. Subject to approval by the shareholders of the Company, effective March 1, 1994, the first sentence of Section 4.5 of the Plan is hereby deleted in its entirety and the following new sentence is substituted in its place: Notwithstanding any other provision of this Plan, no Employee may purchase in an Option Period more than the number of shares equal to 10% of his annual basic rate of compensation divided by 85% of the fair market value of Stock, both determined on the last day of the Option Period. Except as amended above, the Plan shall remain in full force and effect according to its terms and provisions. Done this the 25th day of August, 1993. NICHOLS RESEARCH CORPORATION Chris H. Horgen By:____________________________________ Its Chief Executive Officer AMENDMENT NUMBER SIX TO THE NICHOLS RESEARCH CORPORATION 1988 EMPLOYEES' STOCK PURCHASE PLAN Pursuant to Section 7.1 of the Nichols Research Corporation 1988 Employees' Stock Purchase Plan (the "Plan"), Nichols Research Corporation (the "Company"), hereby amends the Plan as follows: 1. Subject to approval by the shareholders of the Company, effective November 1, 1996, Section 7.1 of the Plan is hereby deleted in its entirety and the following new Section 7.1 is substituted in its place: 7.1 AMENDMENT. The Board of Directors, insofar as permitted by law, shall have the right from time to time with respect to any shares at the time not subject to options, to suspend or discontinue the Plan or revise or amend it in any respect whatsoever, except that without approval of the shareholders of the Company, no such revision or amendment shall: (a) increase (except as provided in Section 4.7) the number of shares of stock available for purchase under the Plan, or (b) remove the administration of the Plan from the Committee. 2. Subject to approval by the shareholders of the Company, effective November 1, 1996, the first two sentences of ARTICLE VIII of the Plan are hereby deleted in their entirety and the following sentences are substituted in their place: The Plan shall be administered by a committee (the "Committee") composed of the entire Board of Directors or a committee of the Board of Directors that is composed solely of two or more Non-Employee Directors. For this purpose, the term "Non-Employee Director" shall mean a person who is a member of the Company's Board of Directors who (a) is not currently an officer or employee of the Company or any parent or subsidiary of the Company, (b) does not directly or indirectly receive compensation for serving as a consultant or in any other non-director capacity from the Company or any parent or subsidiary of the Company that exceeds the dollar amount for which disclosure would be required pursuant to Item 404(a) of Regulation S-K promulgated under the Securities Act of 1933 and the Securities Exchange Act of 1934 ("Regulation S-K"), (c) does not possess an interest in any other transaction with the Company or any parent or subsidiary of the Company for which disclosure would be required pursuant to Item 404(a) of Regulation S-K, and (d) is not engaged in a business relationship with the Company or any parent or subsidiary of the Company which would be disclosable under Item 404(b) of Regulation S-K. In the event the Committee is a committee composed of two or more Non-Employee Directors, the Board of Directors may from time to time remove members from, add members to, and fill vacancies, on the Committee. A member of the Committee shall be eligible to participate in the Plan and receive options under the Plan. Except as amended above, the Plan shall remain in full force and effect according to its terms and provisions. Done this the 14th day of November, 1996. NICHOLS RESEARCH CORPORATION Chris H. Horgen By:____________________________________ Its Chief Executive Officer