penny, Who decides on a up-listing depends on the circumstances. If you have a small company and wanted listed but too small for the big exchanges you would try to secure a market maker to make a market for your shares on the pink sheets. If you are a company like Lehman and don't care if the shares are listed, then if the market maker wants to make a market then the MM decides.
If the stock has no MM support, then it moves to the greys. If one thought a company was behind the listing, one should ask themselves why any stock would go to the grey market. Obviously a company would always want their company on the pink sheets or better.
Grey Market
Securities that are not listed on any stock exchange nor formally quoted on OTC Markets or OTCBB are considered to be in the Grey Market. Unsolicited transactions are processed independently and not centrally listed or quoted. Trades are reported to a self-regulatory organization (SRO), which then passes the data on to market data companies.
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