This forum is to discuss different features/issues of Oracle Financials modules ( GL - General Ledger, AP - Accounts Payable, AR - Accounts Receivable, FA - Fixed Assets & CM - Cash Management ).
One GL is enough for u r three Ou's. One LE can consist Number ou's..so one is enough. coming to sub ledgers u need to define 3 responsibilites to each OU. All operations will be done in OU Level.