Government filings of Donald Trump’s pick for secretary of state Rex Tillerson show that he has up to half a billion dollars worth of assets distributed across an array of investments.
Tillerson’s interests at Exxon Mobil (XOM)—where he was Chairman and CEO until Jan 1—constitute around $300 million of his asset base, the Wall Street Journal reports. A financial disclosure form released by the Office of Government Ethics on Wednesday detailed further assets worth between $50 million and $200 million.
Details on the magnitude of Tillerson’s holdings come at a time of heightened attention on potential conflicts of interest among members of Trump’s incoming cabinet. The ties between Russian President Vladimir Putin and the former-Exxon chief, in particular, have ruffled lawmaker feathers on both sides of the aisle.
Tillerson reportedly mooted strategies for avoiding conflicts of interest in a 9-page letter that accompanied his 38-page financial disclosure. However, scrutiny of his Russia related assets—and his plans for their divestment—is likely to intensify when he appears for Senate confirmation hearings next Wednesday and Thursday.
For more on Rex Tillerson, watch Fortune’s video:
According to his disclosure, WSJ reports, Tillerson investments outside of Exxon include shares in the company’s Big Oil rivals Chevron (CVX), Royal Dutch Shell (RDS-A), and Total (TOT), as well as in blue-chip stocks such as Apple (AAPL) and J.P. Morgan Chase @(JPM).
On Thursday, The Associated Press reported that Tillerson is set to receive a $180 million retirement package from Exxon if he is confirmed as Trump’s secretary of state—that’s equivalent to the value of the over 2 million deferred shares he would have received over the next 10 years.