Bruenn v. Cole (165 A.D.2d 443, [1st Dept 1991]), involved the right to purchase the shares allocated to an apartment in a cooperative conversion, the Court discussed the criteria to be applied in determining whether a tenancy is bona fide or illusory. It concluded that the extent of protection intended to be afforded by the rent regulatory statutes, the intent of the asserted tenant to resume occupancy of the premises and the degree of control by the tenant are relevant factors to be considered in assessing the nature of the tenancy. A court is required to examine the bona fides of the tenancy of the person asserted to hold the status of prime tenant over the party in occupancy as subtenant. The animus reventendi, or intention to return, to the premises remains the criterion by which a tenant is judged to have conveyed a sublease and retained a reversionary interest, or has abandoned any reversionary interest in the leasehold. The length of time for which a tenant has relinquished occupancy of the premises is a salient consideration. Another factor in determining the relationship between the parties is the degree of control over the subject premises exercised by the tenant vis-a-vis the landlord or landlord's agent. In other words, is it the landlord or the prime tenant that exercises dominion and control over the premises. A finding that the prime tenant may have occupied the premises at some time does not preclude a finding that the tenancy is illusory.