Possession : The actual, physical Possession , or the constructive Possession (which  shall be found only if the Person has exclusive control or intends to exercise control  over the Prohibited Substance or Prohibited Method or the premises in which a  Prohibited Substance or Prohibited Method exists); provided, however, that if the  Person does not have exclusive control over the Prohibited Substance or Prohibited  Method or the premises in which a Prohibited Substance or Prohibited Method exists,  constructive Possession shall only be found if the Person knew about the presence  of the Prohibited Substance or Prohibited Method and intended to exercise control  over it.