20 CFR §218.3

1. (a)General. If an employee who is entitled to an annuity disappears, the employee annuity ends on the last day of the month before the month of the disappearance.
2. (b)Employee has a current connection.
   1. (1)The Board may pay survivor benefits from the month of the employee's disappearance if both of the following conditions are met at the time of the disappearance:
      1. (i)The employee has a current connection with the railroad industry as defined in part 216 of this chapter, and
      2. (ii)The employee's spouse is entitled, or would have been entitled if he or she had filed an application, to a spouse annuity in the month that the employee disappeared.
   2. (2)If the employee is later found to have been alive during any month for which a survivor annuity was paid, the amount of any incorrect payment must be recovered under the rules of part 255, Erroneous Payments, of this chapter. The incorrect payment is the amount of any survivor benefits which were paid minus any spouse benefits which were paid minus any spouse benefits that would have been paid.
3. (c)Employee has no current connection. If the employee does not have a current connection and the employee's spouse is entitled to an annuity in the month of the employee's disappearance, the spouse annuity will continue to be paid until one of the following events occurs:
   1. (1)The employee's death is established.
   2. (2)The spouse annuity ends for another reason.