Hi Maria,
If you want that the batch determination consider the subcontracting stock, first, the special stock indicator must be assigned in the materiai. Then, you must check if the batch is classified, I mean, in MSC2n transaction the tab Classification must be correctly fulfilled.
Of course, there are those settings related to search strategy and selection criteria that should be taken into consideration. However, if your system already finds batches that are not from a subcontractor, the special stock flag should be enough.
Just and additional information, the batch determination happens in Functon Module VB_BATCH_DETERMINARION. If you are familiar with DEBUG, you can easily find important logic and information inside of this function.
Best Regards,
Ricardo Dias