Can a security be traded on the OTC Bulletin Board (OTCBB) and Nasdaq at the same time?
No. The OTCBB is a quotation service for securities which are not listed or traded on Nasdaq or a national securities exchange. It is possible, however, for a security to list or delist from Nasdaq intraday, and therefore move from the OTCBB to Nasdaq or from Nasdaq to the OTCBB during the same trading day.