Okay say Indonesia for example, here is a list of all the public companies that trade on their exchange: http://www.idx.co.id/en-us/home/listedcompanies/listingactivity.aspx Now take a look at the oatsreportable list which represents ALL stocks that are able to be purchased on the US market whether listed or unlisted. http://oatsreportable.finra.org/oatsreportablesecurities-SOD.txt Now explain why so many Indonesian stocks are not on this list...