If interest on U.S. savings bonds, series EE or I, hasn’t been reported annually, then the accrued interest becomes fully taxable when the bonds are redeemed. This income is ordinary interest income; it is not a capital gain. The financial institution at which you cash in the bonds will issue Form 1099-INT to report the interest income to you (and to the IRS).
An unincorporated business or income-producing entity organized by two or more persons. A partnership is not subject to tax but passes through to the partners all income, deductions, and credits, according to the terms of the partnership agreement.