Section 4050.203 - Options and duties of plan(a)Options. A subpart B plan that is closing out upon plan termination may (but need not) elect, by filing under § 4050.205 , that the subpart B plan-(1) Will be a "transferring plan," that is, will pay a benefit transfer amount to PBGC for each distributee who is missing upon close-out of the plan and will be bound by the provisions of this subpart B to the extent that they apply to transferring plans, or(2) Will be a "notifying plan," that is, will notify PBGC of the disposition of the benefits of each distributee identified in the filing who is missing upon close-out of the plan and will, with respect to those distributees, be bound by the provisions of this subpart B to the extent that they apply to notifying plans.(b)Diligent search -(1)In general. Except as provided in paragraph (b)(2) of this section, for each distributee whose location the plan does not know with reasonable certainty upon close-out of a subpart B plan, the plan must have conducted a diligent search as described in § 4050.204 .(2)Notifying plans. For a notifying plan, the requirement of paragraph (b)(1) of this section applies only to distributees identified in the filing with PBGC.(c)Filing with PBGC - (1)In general. Except as provided in paragraph (c)(2) of this section, for each distributee who is missing upon close-out of a subpart B plan, the plan must file with PBGC as described in § 4050.205 .(2)Notifying plans. For a notifying plan, the requirement of paragraph (c)(1) of this section applies only to distributees identified in the filing with PBGC.