Common ownership

[Guest Pat Metallic]

Dr. A is 100% owner of Company A (no other employees)

Dr. B is 100% owner of Company B

Both doctors are 50% owners each of Company C

They have a SEP for the employees of Company C. Can Dr. A have a uni-(k) for himself in Company A? As a side note, he currently is benefitting from Company C's SEP.

[BeckyMiller]

You need to look at the rules in IRC Section 414 - specifically (b), © and (m). Physician groups frequently get aggregated under section 414(m) because of the affiliated service group rules. Thus, even if they don't meet the general five or fewer 80/50 standard, they can still be considered a single employer.