U.S. Senate Democrat unveils 'billionaires tax' for Biden agenda

U.S. billionaires would pay tax on unrealized gains from their assets to help finance President Joe Biden's emerging social-policy and climate-change legislation, according to a proposal unveiled on Wednesday by the top Senate Democrat for tax policy.

The so-called billionaires tax, announced by Senate Finance Committee Chairman Ron Wyden, is part of a two-pronged legislative strategy that also includes a proposed 15% corporate minimum tax on the most profitable U.S. corporations, which was unveiled on Tuesday.

Wyden and other lawmakers, including Democratic Senator Elizabeth Warren, say the legislation is intended to curtail...