Was M1 employed by M2 , employed by M3 , and employed by a actor 's employer
SELECT count(*) WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
?x1 a ns:film.actor .
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
}