I use dex2 manager in COM API to request ISIN and SEDOL fields:

Sample code:

            HRESULT l_hr = m_RData->put_InstrumentIDList(CComVariant(a_InstrumentIDList));
            if (l_hr == S_OK)
            {
                l_hr = m_RData->put_FieldList(CComVariant(a_FieldList));
                if (l_hr == S_OK)
                {
                    l_hr = m_RData->put_RequestParam(CComVariant(a_RequestParam));
                    if (l_hr == S_OK)
                    {
                        l_hr = m_RData->put_DisplayParam(CComVariant(a_DisplayParam));
                    }
                    else
                    {
                        wstring w_request(a_RequestParam);
                        string error("[EikonComDex2] Couldn't set the RequestParam: " +
                            string(w_request.begin(), w_request.end()));
                        m_logger->Log(error, DCLogger::DC_LOG_LEVEL_ERROR);
                        DataCollectorHelper::CoutLog(error, DC_RED);
                    }
                }
                else
                {
                    wstring w_fields(a_FieldList);
                    string error("[EikonComDex2] Couldn't set the FieldList: " +
                        string(w_fields.begin(), w_fields.end()));
                    m_logger->Log(error, DCLogger::DC_LOG_LEVEL_ERROR);
                    DataCollectorHelper::CoutLog(error, DC_RED);
                }
            }

a_InstrumentIDList : 1 RIC or comma separated RICs

a_FieldList : "TR.ISIN,TR.SEDOL"

a_DisplayParam: "RH:In"

If instrument list is "FROG.OQ", I receive:

'FROG.OQ','IL0011684185','BMX6JW3'

If instrument list is ",FROG.OQ" , I receive:

'FROG.OQ',IL0011684185,'BMX6JW3'
'FROG.OQ','null','BMX6JW3'

If instrument list is ",,,FROG.OQ" , I receive:

RIC field is invalid
RIC field is invalid
'FROG.OQ',IL0011684185,'BMX6JW3'
'FROG.OQ','null','BMX6JW3'

This is reproducible. Could you check if this is a bug?

Second case:

If instrument list is "ACET.OQ", I receive:

'ACET.OQ','US0070021086','BMC5RV6'
'ACET.OQ','US0070021086',null

Thanks