Remember that the Sublandlord cannot give the subtenant more rights than the landlord gave him under the master lease agreement. For example, a master lease could allow a tenant to use a property as a dental office. If this master lease agreement creates a sublease, the tenant can only use the space as a dental practice. In this case, the tenant (now the Sublandlord) does not violate the terms of the master rental agreement because it does not insert the new tenant more rights than what was originally provided. However, if the subtenant wished to open another type of business such as a retail business, the Sublandlord would not be able to authorize it without the written consent of the owner.