Senator Lummis’s amendment proposed taxing mining, staking, airdrop and forked assets only upon sale, aligning tax policy with actual income realization rather than receipt

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This aligns the taxation of mining and staking rewards with the actual realization of economic benefit, rather than forcing recognition based on volatile and often uncertain fair market values at the time of receipt,

Crypto mining works in much the same way, with assets created in the digital mining process and then later sold. Assets gained from aidrops and forks would also get the same treatment under Lummis' amendment, getting taxed only when they're ultimately sold.