Was M3 founded by a screenwriter and founded by a editor of M1 and M2
SELECT count(*) WHERE {
?x0 a ns:film.writer .
?x1 ns:film.editor.film M1 .
?x1 ns:film.editor.film M2 .
M3 ns:organization.organization.founders ?x0 .
M3 ns:organization.organization.founders ?x1
}