We would continue to have traditional employees, on whose wages employers must withhold Social Security tax and Medicare tax, and remit it to the Internal Revenue Service, with employer matching Social Security tax and Medicare tax.

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The alleged scammers use the stolen Social Security numbers to file fake documents from companies purporting to withhold tax, then fake returns that are structured to ensure the filer is owed a refund.

WSJ: Billions Lost in Tax-Refund Scam

Other reasons to file include when you own special taxes like the alternative minimum tax (AMT), household employment taxes, taxes on retirement accounts or Social Security and Medicare tax on tips you did not report to your employer or on wages from an employer who did not withhold those taxes.

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