question: Was M2 acquired by M3 , M4 , and M5 , acquired by a company , and acquired by M1 's employer
query: SELECT count(*) WHERE {
  ?x0 a ns:business.employer .
  ?x1 ns:business.employer.employees/ns:business.employment_tenure.person M1 .
  M2 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x0 .
  M2 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x1 .
  M2 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3 .
  M2 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M4 .
  M2 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M5
  }