With an annual salary of roughly $6.3m (£4.9m) per year, Christopher Wray is a rarity among Big Law equity partners, particularly for partners at Atlanta-based firms.

Wray, the Trump administration's nominee to replace fired FBI director James Comey, chairs King & Spalding's special matters and government investigations practice, a key area for his firm.

This week, ahead of his confirmation hearing before the Senate Judiciary Committee, Wray, 50, disclosed that the firm had paid him $9.2m (£7.2m) from the beginning of 2016 through mid-June.

That works out to an average of $528,000 (£411,000) per month, or $6.3m (£4.9m) annually.

Jeffrey Lowe, who heads Major Lindsey & Africa's global legal recruiting practice, said the figure sounds extraordinarily high because it is. Lowe authors a survey of partner compensation at the largest firms in the US, in conjunction with ALM Legal Intelligence. Despite rising partner profits at many top firms, he said very few partners make more than $5m (£3.9m), especially outside the Wall Street elite.

"That's why they're the unicorns," Lowe said. And when it comes to Wray, Lowe said: "He's got a pretty big horn."

"I would estimate that he's in the top 10% of the top 1%," he added. "He's as rare as you would think he is."

Of the 2,137 US partners (equity and non-equity) from Am Law 200, NLJ 350 and Global 100 firms who responded to Major Lindsey's 2016 partner compensation survey, only five reported compensation of more than $8m. The survey reports compensation anonymously.

King & Spalding chairman Robert Hays declined to comment on Wray's salary.

Lowe said practice areas for partners in this elite $5m-plus circle would be "top M&A people, top white-collar people, various intellectual property litigators". He added: "Definitely what he's doing is where you'd see people at this compensation level, who are at the very top of their game."

Washington, where Wray has an office, is a city full of high-powered white-collar defence practitioners, but "even in DC that's a big, big number", said Lowe, who heads Major Lindsey's Washington office.

Wray has been a partner at King & Spalding for nearly 12 years, following eight years at the Department of Justice, where he led the criminal division from 2003 to 2005, overseeing more than 400 prosecutors. His private practice clients have included SunTrust Bank, Wells Fargo, Wachovia, Credit Suisse, Chevron, Johnson & Johnson, Janssen Pharmaceuticals, Medtronic, Georgia-Pacific, and New Jersey Governor Chris Christie.

Wray's paycheck is even more notable given that he works partly out of Atlanta, a less pricey legal market than Washington and a far cry from New York.

With average profit per partner (PEP) of $2.47m (£1.9m) last year, King & Spalding is already near the pinnacle of partner pay among the highest-grossing firms in the US. The firm ranks 21st by PEP in the Am Law 100.

Wray is likely to be at the top of King & Spalding's partner compensation scale, outpacing the average equity partner by a factor of about 2.6. (King & Spalding has about 200 equity partners.)

Lowe said a lot of firms set caps on what their partners can make. "Not that they are any less successful or profitable – but they've made the decision to have less of a partnership [compensation] spread," he said.

"There are only a handful of firms where the number can be unlimited," he added, "but even [at firms] with caps, there are some outliers."

"Even a firm well down the Am Law 100 may have a guy making this much money, if he has a massive practice," Lowe said. "It's a very competitive market, so to keep that person a firm might have to break its compensation scale."

Even beyond Atlanta, only a handful of partners with Wray's level of government experience are known to have made it into the $5m-plus salary club. For comparison, when Jeh Johnson became Homeland Security secretary in 2013, he reported income from Paul Weiss Rifkind Wharton & Garrison of $2.45m. Johnson had previously been Defence Department general counsel before he returned to the firm for a year.

Eric Holder disclosed that Covington & Burling paid him $2.15m in 2008 and $2.5m in 2009. He worked at the firm between his tenure as deputy attorney general during the Clinton administration and as President Barack Obama's first attorney general.

Former US solicitor general Paul Clement was rumored to earn $5m at King & Spalding before he left the firm in 2011. (Clement moved his boutique appellate firm to Kirkland & Ellis last year in a deal that likely drew more.) Similarly, former Securities and Exchange Commission enforcement director Robert Khuzami earned headlines in 2013 when he joined Kirkland & Ellis for $5m a year.

The following year, Kirkland hired Chicago litigation partner James Hurst away from Weil Gotshal & Manges for $9m annually.

In the Trump administration, top lawyers joining from private practice were fetching less. For instance, White House counsel Donald McGahn and deputy counsel Gregory Katsas made $2.4m and $3.9m, respectively, at Jones Day last year.

Assuming Wray is confirmed as FBI director, his salary will drop quite a bit. As a Level 3 position, according to the Office of Personnel Management, the FBI director job pays $172,100 per year—just under the $180,000 starting salary for a first-year associate in King & Spalding's Washington office.