Vesting under acquisition

[Guest jmlumpkin]

Company B maintains a qualified 401(k) plan. Company A acquires Company B with the intention of continuing Company B's plan. Please confirm, citing any references, that the participants under the plan would not become fully vested as a result of the transaction.

I'm fairly certain that this is an event that would not accelerate vesting, but I would like a reference to see it in print.

Thanks.

[Mike Preston]

Participants become vested in two circumstances: partial termination or plan termination. I don't see either of these here, do you? There is an old ruling that calls for vesting if there is an increased likelihood of reversion, but that hasn't happened, either, has it?