Controlled Group / ASG Question

This may be basic but I just wanted to make sure no employees get inadvertently excluded.  Company A is 100% owned by John; Company B is 100% owned by Fred; John and Fred each have 50% ownership in Company C.  All three companies refer business to each other and work together in providing services to common clients.  If Company A wants to sponsor a qualified plan, all three companies would be members of an ASG and would have to all be covered by Company A's plan - is that correct? 

Unless it's a management group relationship, you need some ownership overlap for an ASG, so you most likely do not have an ASG.

So then only Companies A and C would be members of an ASG, as none of the companies provide management services.