question: What company that M4 and M5 acquired and M6 and M7 were acquired by did M1 , M2 , and M3 found
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:business.employer .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M4 .
  ?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M5 .
  ?x0 ns:organization.organization.companies_acquired/ns:business.acquisition.company_acquired M6 .
  ?x0 ns:organization.organization.companies_acquired/ns:business.acquisition.company_acquired M7 .
  ?x0 ns:organization.organization.founders M1 .
  ?x0 ns:organization.organization.founders M2 .
  ?x0 ns:organization.organization.founders M3
  }