Equity crowdfunding calls for the general public to be able to invest in the securities of small businesses and startups listed on the crowdfunding platforms (provided they meet certain financial requirements), but for now these securities are only available to accredited investors.

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However, Arca wouldn't be able to trade NYSE-listed securities, taking one of the 13 U.S. stock exchanges out of the loop for brokers, according to persons familiar with the plan's working.

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Consider for example the recent decision of the Securities and Futures Commission of Hong Kong to allow shares of the United Company RUSAL to be listed on the Hong Kong Stock Exchange.

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Most portfolio investments consist of investment in securities in the primary and secondary markets, including shares, debentures and warrants of companies listed or to be listed on a recognized stock exchange in India.

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