as per section 141(3)(e) of the Companies Act 2013
The following persons shall not be eligible for appointment as an auditor of a company, namely:
a person or a firm who, whether directly or indirectly, has business relationship with the company, or its subsidiary, or its holding or associate company or subsidiary of such holding company or associate company of such nature as may be prescribed;
But company X and Y not following under above section as they are not in any relation except having one comman director who is C.A. still firm is not eligible?