Yes, but there are many types of securities on the grey market. You need to look at any and all suspended pinks to get a sense of their grey sheet performance as a whole. You can't compare them to ADRs or any symbol that ends in an "F" which is generally a foreign company that does not file with the SEC. Also MANY stocks start out on the greys. They are also VERY different than a pink that has been suspended and knocked down to the greys.
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