To protect the network, users mining through open pools should refrain from using a pool if it starts uncle mining.
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DwarfPool
Mined uncles last 24h 170
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So dwarfpool is the only pool with enough resources to perform the uncle mining attack.
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Because the current average number of uncles per block is as low as 7%, we know no mining pool is currently taking advantage of the problem.
RE: Uncle Mining, an Ethereum Consensus Protocol Flaw