What employer of M0 and M1 did M2 and M3 acquire
SELECT DISTINCT ?x0 WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M0 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M1 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3
}