(A) As used in this section:

1. (1) "State retirement system" means the public employees retirement system, school employees retirement system, or state teachers retirement system.
2. (2) "Total service credit" means all service credit earned in the state retirement systems, except credit for service subject to section 145.38 of the Revised Code. Total service credit shall not exceed one year of credit for any twelve-month period.
3. (3) In addition to the meaning given in division (N) of section 145.01 of the Revised Code, "disability benefit" means "disability benefit" as defined in sections 3307.01 and 3309.01 of the Revised Code.

(B) To coordinate and integrate membership in the state retirement systems, the following provisions apply:

1. (1) Subject to division (B)(2) of this section, at the election of a member, total contributions and service credit in all state retirement systems, including amounts paid to restore service credit under sections 145.311, 3307.711, and 3309.261 of the Revised Code, shall be used in determining the eligibility and total retirement or disability benefit payable. When total contributions and service credit are so combined, the following provisions apply:

   1. (a) Age and service retirement shall be effective on the first day of the month immediately following the later of:

      1. (i) The last day for which compensation was paid;
      2. (ii) The attainment of minimum age or service credit eligibility for benefits provided under this section;
      3. (iii) Ninety days prior to receipt by the board of the member's completed application for retirement.

   2. (b) Disability benefits shall be effective on the first day of the month immediately following the later of the following:

      1. (i) The last day for which compensation was paid;
      2. (ii) The attainment of eligibility for a disability benefit.
   3. (c) Eligibility for a disability benefit shall be determined by the board of the state retirement system that will calculate and pay the benefit, as provided in division (B)(1)(d) of this section. The state retirement system calculating and paying the disability benefit shall certify the determination to the board of each other state retirement system in which the member has service credit and shall be accepted by that board as sufficient for granting a disability benefit.
   4. (d) The board of the state retirement system in which the member had the greatest service credit, without adjustment, shall calculate and pay the total retirement or disability benefit. Where the member's credit is equal in two or more state retirement systems, the system having the largest total contributions of the member shall calculate and pay the total benefit.
   5. (e) In determining the total credit to be used in calculating a retirement or disability benefit, total combined service credit shall not exceed one year of credit for any one "year" as defined in the law of the system making the calculation.

   6. (f) The state retirement system calculating and paying a retirement or disability benefit shall receive from the other system or systems all of the following for each year of service:

      1. (i) The amount contributed by the member, or, in the case of service credit purchased by the member, paid by the member, that is attributable to the year of service;
      2. (ii) An amount equal to the lesser of the employer's contributions made on behalf of the member to the retirement system for that year of service or the amount that would have been contributed by the employer for the service had the member been a member of the public employees retirement system at the time the credit was earned;
      3. (iii) Interest compounded annually on the amounts specified in divisions (B)(1)(f)(i) and (ii) of this section at the lesser of the actuarial assumption rate for that year of the retirement system determining and paying the benefit or the other retirement system or systems transferring amounts under this section. If applicable, the public employees retirement system shall pay to the retirement system calculating and paying the benefit a portion of the amount paid on behalf of the member by an employer under section 145.483 of the Revised Code. The portion shall be paid from the employers' accumulation fund and shall equal the product obtained by multiplying by two the amount the member would have contributed during the period the employer failed to deduct contributions, as described in section 145.483 of the Revised Code.
   7. (g) The annuity rates and mortality tables of the state retirement system making the calculation and paying the benefit shall be exclusively applicable.
   8. (h) Deposits made for the purpose of an additional annuity, together with earnings as provided in section 145.62 of the Revised Code, upon the request of the member, shall be transferred to the state retirement system paying the benefit. The return upon such deposits shall be that offered by the state retirement system making the calculation and paying the benefit.
2. (2) A former member receiving a retirement or disability benefit under this section, who accepts employment amenable to coverage in any state retirement system that participated in the former member's combined benefit, shall be subject to the applicable provisions of law governing such re-employment. If a former member should be paid any amount in a retirement benefit, to which the former member is not entitled under the applicable provisions of law governing such re-employment, such amount shall be recovered by the state retirement system paying such benefit by utilizing any recovery procedure available under the code provisions of the state retirement system covering such re-employment.