Did a film producer employed by M1 , employed by M2 , and employed by M3 play M4
SELECT count(*) WHERE {
?x0 a ns:film.producer .
?x0 ns:film.actor.film/ns:film.performance.character M4 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M3
}