A DB Plan has 3 active participants, the two owners (husband and wife) and their son. Is this plan required to be covered by PBGC?

If the son does not own stock on his own - yes. Unless the company meets one of the special exemptions on its own - dr, lawyer, accountant, certain professionals, etc.

Don't the attribution laws apply? If his parents attribute their ownership to him, then they are all substantial owners...

The 1563 attribution rules apply and I believe the son would have to own 50% or more of the company to be attributed his parents ownership - in which case he would be a substantial owner already. So, the plan is definitely PBGC covered.

You're right. Thank you for verification!!
http://www.tagdata.com/quotes/pbgc-premium-payment.htm

The 1563 attribution rules apply to corporation. What type of business sponsors this DB plan? How old is their son?

The type of business is irrelevant. Ownership for PBGC purposes considers 1563 attribution.

No one has mentioned the age of the son. He is attributed his parents' ownership until age 21. Since a substantial owner is someone who doesn't have 10%+ in the last 5 years, the plan doesn't become PBGC covered until the son reaches age 26. Happy birthday.

The type of business is important. Partnership or LLC that employs a son who is a non-owner will be covered by PBGC.

Hmm, it appears you are right. The reference to 1563 is just regarding corporations.

So, how long until VEBAPLAN writes his favorite word? He must be busy filming another video. Probably about balloon rides and the aftereffects.

Given the exemption to 404 combined plan deduction limits if covered by PBGC, that $102 check per year may not exactly be the worst thing in the world in this circumstance.