Washington (CNN) -- Labor unions must give nonmember workers "fresh notice" of unplanned increases in fees or assessments -- money that might be used for political purposes -- the Supreme Court ruled Thursday.

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The government has already given notice that it will ban referral fees and limit legal fees, but Aviva believes the cost could be cut further by putting a claim first to the "at fault" insurer.

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Knox reaffirmed and extended this principle, holding that if a union wishes to assess money in addition to its regular fees, it must not only provide employees with notice but must also make the system opt-in rather than opt-out.

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Ever notice how Wall Street solutions always involve more fees?

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If you book a flight today on the low-fare carrier Allegiant Air, www.allegiantair.com, you will notice that it bumps up the round-trip total by adding taxes and fees.

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The second disclosure, a quarterly notice first due out in November, will detail how much you are personally paying in fees, including charges related to any 401(k) loans.

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