What was acquired by M0 , acquired by M1 , acquired by a company , and acquired by M2
SELECT DISTINCT ?x0 WHERE {
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x1 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M0 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M1 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
?x1 a ns:business.employer
}