Was a film 's editor employed by M0 and M1 and employed by M2 and M3
SELECT count(*) WHERE {
?x0 ns:film.editor.film ?x1 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M0 .
?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 .
?x1 a ns:film.film
}