Story highlights Nominees must obtain OGE's certification of their financial disclosure reports

OGE said it would "continue expediting our ethics reviews of the President-elect's nominees to meet reasonable time frames"

Washington (CNN) Several of the wealthiest nominees for top Cabinet posts are headed to Capitol Hill for confirmation hearings this week, but the clock is ticking for them to complete the ethics and financial review process.

Of the current list of 21 nominees, 14 must still sit for Senate hearings, and only five of those 14 have finalized their required paperwork.

All nominees for Senate-confirmed positions must first work with the Office of Government Ethics to devise a plan for resolving any financial conflicts of interest before they start their new jobs. Typically, the ethics office sends the Senate a package with the nominee's ethics agreement, a financial disclosure report and a cover letter certifying the report after all potential conflicts are addressed, and then posts the forms on its website roughly a day later.

But the paperwork for two of President-elect Donald Trump's billionaire nominees with hearings scheduled for this week -- namely, Education Secretary-designate Betsy DeVos (up Tuesday) and Commerce Secretary-designate Wilbur Ross (up Wednesday) -- were notably missing from the ethics office's website as of Monday afternoon.

DeVos is an heir to the Amway fortune and Ross is an investor who made his money buying up distressed companies.

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