What employer of M1 , M2 , M3 , and M4 did M0 found
SELECT DISTINCT ?x0 WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M1 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M2 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M3 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M4 .
?x0 ns:organization.organization.founders M0
}