The large OTC stocks are 1) not penny stocks prohibited to be invested in by mutual funds and institutional investors, NWBO is not in that category; and 2) NWBO is not yet a true company in that sense as a pre-revenue biotech still in the stage of validating its product.
I think they will uplist to get that investment and validation. I think it is a key path and they need to do it. Some of the companies to which you refer are also international companies from other countries and are also on their own National exchanges and the OTC listing is a convenience for institutions here, but they are not really seen therefore as “OTC” stocks. It’s not their only exchange or their primary exchange. Others are major economic players in US markets, like mortgage markets.