question: Was M1 acquired by M2 , M3 , M4 , and M5 and acquired by M0 's founder 's employer
query: SELECT count(*) WHERE {
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
  ?x1 ns:organization.organization_founder.organizations_founded M0 .
  M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x0 .
  M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
  M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3 .
  M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M4 .
  M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M5
  }