Investment Tax Incentive Act of 2003

Investment Tax Incentive Act of 2003 - Amends the Internal Revenue Code to provide for reduced capital gain rates for qualified economic stimulus gain. Defines "qualified economic stimulus gain" as the aggregate long-term capital gain (with specified exceptions) from property the holding period for which begins during the 2-year period beginning on the date of the enactment.

Provides for the indexing of assets (certain stocks and tangible property) for purposes of determining gain or loss.