Among them: hedge funds, untraded securities, foreign-exchange contracts, precious-metal bullion, tax liens, natural-gas wells, private mortgages and other secured debt, movie partnerships, cattle, fishing rights and even investments in bull semen.

WSJ: IRAs Get Sexier

Apple's figures for foreign tax appear on page 61 of its form 10-K filing with the US Securities and Exchange Commission (SEC).

BBC: Apple paid only 2% corporation tax outside US

The Municipal Securities Rulemaking Board, a self-regulatory body that reports to the Securities and Exchange Commission, has proposed rules that would require brokers to ask clients about the importance of state tax benefits, explain a client's direct-sold in-state plan for comparison purposes, and determine what is most suitable for the client--instead of just pushing broker-sold out-of-state plans that might carry higher commissions for them.

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