Section 28-408.6.4. Ownership limitations

An  individual who is a licensed
  master plumber whose interest or ownership in a master plumber  business
  constitutes  any  portion of the 51 percent interest or control required
  by this section 28-408.6 shall be prohibited from possessing an interest
  or ownership in more than one other master plumber business  at  his  or
  her  established  place  of  business,  where such interest or ownership
  would constitute any portion of  the  51  percent  interest  or  control
  required  by  this  section  28-408.6. Both master plumber businesses in
  which the individual who is a licensed master plumber  has  an  interest
  shall be located at the same place of business. For the purposes of this
  section  28-408.6, where two or more individuals who are licensed master
  plumbers possess an interest or ownership in any master plumber business
  which together represents more  than  51  percent  of  the  interest  or
  control of such entity, all of such licensees shall be deemed to possess
  a portion of the 51 percent interest or control required by this section
  28-408.6.