Two Senate Democrats say Rex Tillerson’s plan to eliminate conflicts of interest stemming from his ties to Exxon Mobil before becoming President-elect Trump’s secretary of state should be illegal, despite Tillerson’s efforts to sever ties with the energy giant.

Sens. Elizabeth Warren of Massachusetts and Tammy Baldwin of Wisconsin called Tillerson’s plan to divest himself of about $180 million in deferred Exxon shares a “golden parachute” Wednesday night. Under legislation proposed by Baldwin meant to reform the “revolving door” between industry and the government, the plan would be illegal, the senators noted.