question: Was a person that M2 was founded by , M3 was founded by , and M4 was founded by M1 's employee
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x0 ns:organization.organization_founder.organizations_founded M2 .
  ?x0 ns:organization.organization_founder.organizations_founded M3 .
  ?x0 ns:organization.organization_founder.organizations_founded M4 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1
  }