Was M1 employed by M2 , employed by M3 , M4 , and M5 , and employed by a employer of M0
SELECT count(*) WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M0 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M4 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M5
}