With respect to the computation of position limits, the positions of all accounts directly or indirectly owned or controlled by a Person or Persons, and the positions of all accounts of any Person or Persons acting in concert and the positions of all accounts in which a Person or Persons have a proprietary or beneficial interest, shall be accumulated and deemed to be positions of each of such Persons as if each owned or controlled all the accumulated positions individually. The Exchange may from time to time provide exemptions to this Rule 4.1.18.