For purposes of these rules, a principal residence has the same meaning as under the Section 121 home sale gain exclusion rules.

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In December it issued temporary rules covering when you can get a partial exclusion if you haven't lived in your home two years and final rules on other issues.

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Index construction methodology has rules for inclusion and exclusion and index constituents change often.

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Gift tax rules are not relevant to the question whether the transfer has the requisite donative intent for the income tax exclusion.

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