Restating a Principal Financial Group non-std prototype plan this morning and could not find a named trustee, but did find this text: "The plan is not trusteed. Plan assets shall be invested only in an annuity contract."
I guess the trustee section of the adoption agreement is left blank, but what about the Schedule P?
You learn something every day in this business. Thanks. Maverick

This is a wild unfounded guess, but what about having the plan's administrative committee sign it?

Why would you file a Schedule P if there is no trust?

MGB is correct. If there is no trust, there is no other entity potentially subject to tax for which you would want to start the limitations period running (which is the only purpose of the Schedule P).