Saudi Arabia announced last July that it would permit direct foreign purchases of shares in the first half of 2015, as a way to expose companies to market discipline, diversify the economy beyond oil and create jobs.
Fund managers believe tens of billions of dollars will eventually enter the country as a result; Saudi Arabia is the Arab world's biggest stock market and one of its most diverse.
In draft rules released last August before a period of public consultation, the CMA proposed a 10 percent cap on foreign ownership of the market's value.
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Among other draft rules, a single foreign investor could own no more than 5 percent of any listed firm, while all foreign institutions combined could own no more than 20 percent.
Up to now, foreign investors have been restricted to buying Saudi shares indirectly through swaps or exchange-traded funds.