Congressional Democrats are considering reforms to the 20% pass-through tax deduction as part of a $3.5 trillion federal spending package.

Democrats’ proposal would phase out the tax break for business owners with taxable income exceeding $400,000, according to a discussion list obtained by CNBC. It would also make the tax cut available to more people below the $400,000 threshold by removing some existing restrictions.

A discussion list is a draft of ideas that lawmakers assemble before formally pitching them in the House or Senate. Democrats are weighing changes to the tax code to help raise money for up to $3.5 trillion in spending on climate, education, paid leave and other measures.