Determination by Accountant All mathematical determinations, and all determinations as to whether any of the Total Payments are "parachute payments" (within the meaning of Section 280G of the Code), that are required to be made under this Section, including determinations as to whether a Gross-Up Payment is required, the amount of such Gross-Up Payment, the reduction of the Total Payments to the Safe Harbor Cap, amounts relevant to the last sentence of this Section 6(b), and the assumptions to be utilized in arriving at such determinations, shall be made at Westport's expense by an independent nationally recognized accounting firm selected by Westport (the "Accounting Firm"). The Accounting Firm shall provide its determination (the "Determination"), together with detailed supporting calculations and documentation to Westport and the Employee by no later than ten (10) days following the Termination Date, if applicable, or such earlier time as is requested by Westport or the Employee (if the Employee reasonably believes that any of the Total Payments may be subject to the Excise Tax). If the Accounting Firm determines that no Excise Tax is payable by the Employee, it shall furnish the Employee and Westport with a written statement that such Accounting Firm has concluded that no Excise Tax is payable (including the reasons therefor) and that the Employee has substantial authority not to report any Excise Tax on his or her federal income tax return. If a Gross-Up Payment is determined to be payable, it shall be paid to the Employee within twenty (20) days after the Determination (and all accompanying calculations and other material supporting the Determination) is delivered to Westport by the Accounting Firm. Any determination by the Accounting Firm shall be binding upon Westport and the Employee, absent manifest error. As a result of uncertainty in the application of Section 4999 of the Code at the time of the Determination by the Accounting Firm hereunder, it is possible that Gross-Up Payments not made by Westport should have been made ("Underpayment"), or that Gross-Up Payments will have been made by Westport which should not have been made ("Overpayments"). In either such event, the Accounting Firm shall determine the amount of the Underpayment or Overpayment that has occurred. In the case of an Underpayment, the amount of such Underpayment shall be promptly paid by Westport to or for the benefit of the Employee. In the case of an Overpayment, the Employee shall, at the direction and expense of Westport, take such steps as are reasonably necessary (including the filing of returns and claims for refund), follow reasonable instructions from, and procedures established by, Westport, and otherwise reasonably cooperate with Westport to correct such Overpayment, provided, however, that (i) the Employee shall not in any event be obligated to return to Westport an amount greater than the net after-tax portion of the Overpayment that he or she has retained or has recovered as a refund from the applicable taxing authorities and (ii) this provision shall be interpreted in a manner consistent with the intent to make the Employee whole, on an after-tax basis, from the application of the Excise Tax, it being understood that the correction of an Overpayment may result in the Employee repaying to Westport an amount which is less than the Overpayment.