In this post we've analyzed a flaw in Ethereum consensus protocol
related to uncle rewards that incentivize miners having more than 12.5%
of the hashing power to do uncle mining. The practical threshold where
uncle mining becomes profitable is between 12.5% and 37%, and more
network analysis is required to find out the current threshold. Uncle
mining is in some ways similar to "selfish" mining, but the word
"selfish" here is misleading since, over certain threshold, uncle
mining benefits all miners. Also the the same flaw allows the majority
of miners in collusion to almost triple the money supply. The flaw is
not critical, but should not be disregarded.