OTC has three explanations. First, the most common explanation is that OTC is the abbreviation of Over The Counter, which refers to the over-the-counter drugs in the pharmaceutical industry; Secondly, over-the-counter trading refers to the spot foreign exchange transactions conducted by the trading subjects in the inter-bank foreign exchange market on the basis of bilateral credit through independent bilateral inquiry and bilateral settlement. Third, in the field of welding equipment, OTC stands for Osaka style in Japan.
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