Making millions by doing absolutely nothing – this sounds too good to be true. If you would advertise your company with this, none would take you serious. But this tagline is very applicable to Bitcoin miners and other cryptocurrency miners. They are making millions without processing one transactions.

The miners of the largest proof-of-work cryptocurrencies – Bitcoin, Litecoin, Dash and Ether – have earned over $18 billion. However, not all blocks contain transactions. Bitcoin Cash miners have processed an impressive 3300 empty blocks since the fork. Litecoin holds the crown for the most processed empty blocks. Block 1586699 had three transactions, totaling less than 1 Litecoin – but the block reward was over $1000.

So far, Bitcoin and Ether are the cryptocurrencies which have the fewest empty blocks, as they are the biggest and most popular proof-of-work blockchains. For others, there are a lot of empty blocks involved. Monero has offered an interesting solution for this: future blocks will all give out the same block reward. There will always be an incentive to mine and the blockchain does not risk a block reward of zero.