plan with respect to its employees, contributions by that employer to a multiemployer defined benefit plan with respect to some or all of the same group of employees shall be deductible under sections 162 and this section, subject to the limits in subparagraph (D). (II) Transition contribution The full amount of a contribution to satisfy the transition contribution requirement (as defined in section 440A(d)) and allocated to the legacy defined benefit plan for the plan year shall be deductible for the employer’s taxable year ending with or within the plan year. . (f) Minimum vesting standards (1) Years of service under composite plans (A) Employee Retirement Income Security Act of 1974 Section 203 of the Employee Retirement Income Security Act of 1974 ( 29 U.S.C. 1053 ) is amended by inserting after subsection (f) the following: (g) Special rules for computing years of service under composite plans (1) In general In determining a qualified employee’s years of service under a composite plan for purposes of this section, the employee’s years of service under a legacy plan shall be treated as years of service earned under the composite plan. For purposes of such determination, a composite plan shall not be treated as a defined benefit plan pursuant to section 801(d). (2) Qualified employee For purposes of this subsection, an employee is a qualified employee if the employee first completes an hour of service under the composite plan (determined without regard to the provisions of this subsection) within the 12-month period immediately preceding or the 24-month period immediately following the date the employee ceased to accrue benefits under the legacy plan. (3) Certification of years of service For purposes of paragraph (1), the plan sponsor of the composite plan shall rely on a written certification by the plan sponsor of the legacy plan of the years of service the qualified employee completed under the defined benefit plan as of the date the employee satisfies the requirements of paragraph (2), disregarding any