If Tenant A subleases his apartment to Tenant B, what is Tenant A's interest called?

When Tenant A subleases his apartment to Tenant B, Tenant A's interest in the property is referred to as a sandwich lease. This term arises because Tenant A is in between the original lease with the landlord and the sublease with Tenant B. In this arrangement, Tenant A retains some rights and responsibilities under the original lease while also creating a new agreement with Tenant B.

It's important to understand that the landlord typically holds the primary lease with Tenant A, which is why Tenant A maintains a level of control over the property during the sublease. The sandwich lease enables Tenant A to derive rental income from Tenant B while still being accountable to the landlord.

Other potential options do not accurately describe Tenant A's interest in this scenario. A master lease typically signifies a broader agreement that controls multiple subleases or tenants, while an original lease refers expressly to the primary agreement between the landlord and Tenant A, and a sub-sublease would imply a further subdivision of the lease that isn’t applicable in this context. Thus, the term "sandwich lease" effectively captures the dual relationships involved for Tenant A in this subleasing situation.