U.S. Rep. Tom Emmer (R-Minn) and a bipartisan group from the House Blockchain Caucus want IRS Commissioner Charles Rettig to change the federal agency’s guidance on how it considers charitable, cryptocurrency donations of more than $5,000, according to a letter sent Thursday.

The Internal Revenue Service currently requires taxpayers to have an IRS appraiser determine the value of their cryptocurrency donations. That differs from the IRS’ guidance on cryptocurrency purchases and sales, which allows taxpayers to calculate their obligations based on free market value.

The Blockchain Caucus’ chairs, Emmer, Darren Soto (D-Fla.), David Schweikert (R-Ariz.) and Bill Foster (D-Ill.), and Caucus members Ted Budd (R-N.C.), Ro Khanna (D-Calif.) and Josh Gottheimer (D-N.J.) signed the letter, which asked Rettig to amend the tax code’s Form 8283, the Noncash Charitable Contributions Form, to allow fair market evaluation for crypto donations.

“I urge the IRS to simplify this unnecessarily, and potentially unintended, complex reporting requirement for cryptocurrency, Emmer wrote, noting that cryptocurrency prices are easy to access via an “exchange or index prices.”

Emmer has been after the IRS to improve its guidance. Last month, he reintroduced legislation that would protect taxpayers from penalties on certain gains or losses on forked assets.

Emmer called the latest IRS guidance in 2019 punitive to investors and “not pragmatic.”