29 CFR §4022.6

1. (a)Except as otherwise provided in this section, an annuity which is payable (or would be payable after a waiting period described in the plan, whether or not the participant is in receipt of other benefits during such waiting period), under the terms of a plan on account of the total and permanent disability of a participant which is expected to last for the life of the participant and which began on or before the termination date is considered to be a pension benefit.
2. (b)In any case in which the PBGC determines that the standards for determining such total and permanent disability under a plan were unreasonable, or were modified in anticipation of termination of the plan, the disability benefits payable to a participant under such standard shall not be guaranteed unless the participant meets the standards of the Social Security Act and the regulations promulgated thereunder for determining total disability.
3. (c)For the purpose of this section, a participant may be required, upon the request of the PBGC, to submit to an examination or to submit proof of continued total and permanent disability. If the PBGC finds that a participant is no longer so disabled, it may suspend, modify, or discontinue the payment of the disability benefit.
4. (d)PPA 2006 bankruptcy termination. In a PPA 2006 bankruptcy termination, “bankruptcy filing date” is substituted for “termination date” in paragraph (a) of this section.