Was a employer of M0 acquired by M1 and M2 and acquired by a company
SELECT count(*) WHERE {
?x0 ns:business.employer.employees/ns:business.employment_tenure.person M0 .
?x0 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x1 .
?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
}