N.Y. Comp. Codes R. & Regs. tit. 9, § 2204.6
(c) No occupant of housing accommodations, other than the tenant, shall be evicted under this section where the rental agreement between the landlord and tenant contemplated the subletting by the tenant of the entire accommodations or a substantial portion thereof or the portion occupied by the subtenant.
(1) Unless otherwise prohibited by occupancy restrictions based upon income limitations pursuant to Federal, State or local law, regulations or other requirements of governmental agencies, notwithstanding the provisions of subdivision (a) of this section, the city rent agency shall not issue an order granting a certificate of eviction, and any member of the tenant's family, as defined in paragraph (3) of this subdivision, shall not be evicted under this section where the tenant has permanently vacated the housing accommodation and such family member has resided with the tenant in the housing accommodation as a primary residence for a period of no less than two years, or where such person is a “senior citizen” or a “disabled person,” as defined in paragraph (3) of this subdivision, for a period of no less than one year, immediately prior to the permanent vacating of the housing accommodation by the tenant, or from the inception of the tenancy or commencement of the relationship, if for less than such periods. The minimum periods of required residency set forth in this subdivision shall not be deemed to be interrupted by any period during which the “family member” temporarily relocates because he or she:
(2) On a form prescribed or a facsimile of such form approved by the city rent agency, a tenant may, at any time, advise the landlord of, or a landlord may at any time, but no more often than once in any 12 months, request from the tenant, the names of all persons other than the tenant who are residing in the housing accommodation, and the following information pertaining to such persons:
(3) For the purposes of this subdivision:
(i) family member is defined as a spouse, son, daughter, stepson, stepdaughter, father, mother, stepfather, stepmother, brother, sister, grandfather, grandmother, grandson, granddaughter, father-in-law, mother-in-law, son-in-law, or daughter-in-law of the tenant; or any other person residing with the tenant in the housing accommodation as a primary residence who can prove emotional and financial commitment, and interdependence between such person and the tenant. Although no single factor shall be solely determinative, evidence which is to be considered in determining whether such emotional and financial commitment and interdependence existed, may include, without limitation, such factors as listed below. In no event would evidence of a sexual relationship between such persons be required or considered.
(d)