question: Which production company was acquired by M1 , M2 , and M3 and was acquired by a company
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.production_company .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x1 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M1 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3 .
  ?x1 a ns:business.employer
  }