House Speaker Paul Ryan collected nearly $500,000 in campaign contributions from Charles Koch and his wife after helping usher through a massive tax reform law.

According to a recent campaign finance report filed Thursday, Koch and his wife Elizabeth each donated $247,7000 to Ryan’s joint fundraising committee.

Five other donors, including billionaire businessmen Jeffery Hildebrand and William Parfet, each contributed $100,000 in the last quarter of 2017, according to the records, which were first reported by the International Business Times.

Billionaires Charles Koch and his brother David Koch run the conservative group Koch Industries, one of the largest private corporations in the U.S.

The Republican tax overhaul plan passed in December benefited Koch Industries, as it cut the corporate tax rate from 35 percent to 21 percent, among other cuts. The legislation then got a boost from the Kochs' multimillion-dollar public relations campaign to highlight its benefits.

And 13 days after it passed, Charles and Elizabeth Koch made the near $500,000 donation to Team Ryan, which raises money for the congressman, the National Republican Congressional Committee and a political action committee run by Ryan.

On the same day, Charles and Elizabeth Koch also each donated $237,000 to the NRCC.

“It looks like House Speaker Ryan is quickly being rewarded for passing this legislation that overwhelmingly benefits the Kochs and billionaires like them,” Adam Smith, spokesman for campaign finance reform nonprofit Every Voice, told IBT.