Did M3 employ a actor that M1 and M2 were founded by
SELECT count(*) WHERE {
?x0 a ns:film.actor .
?x0 ns:organization.organization_founder.organizations_founded M1 .
?x0 ns:organization.organization_founder.organizations_founded M2 .
M3 ns:business.employer.employees/ns:business.employment_tenure.person ?x0
}