Possession : The actual, physical Possession , or the constructive Possession  (which shall be found only if the Person  has ex clusive 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 exerci se control over it.