Excluded Employees - New Company

[Guest tbyrd]

Company A operates a safe harbor 401(k) plan under a standardized adoption agreement with no service or age requirements. In 2002, Company B was created which is owned 80% by Company A. Since Company A is on a standardized plan, is it correct to say that Company B's employees would have had to be covered under A's plan and given the chance to defer along with a safe harbor contribution since there is no entry requirements and they are a controlled group?

If so, and this was not done, is the plan still considered safe harbor with the mix-up?

Any ideas on how to fix?