Was M1 acquired by a company , acquired by M2 , and acquired by M3
SELECT count(*) WHERE {
?x0 a ns:business.employer .
M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company ?x0 .
M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M2 .
M1 ns:organization.organization.acquired_by/ns:business.acquisition.acquiring_company M3
}