What is a Stale Block?
A stale block is a block of data on the blockchain that has been superseded by another, more recent block. This occurs when two miners successfully mine blocks at nearly the same time and one miner’s block becomes accepted by most or all of the network nodes before the other miner’s. The second miner’s work then goes to waste, as it didn’t become part of the longest chain (the one accepted by most or all nodes). The resulting orphaned block is known as a stale block.
Stale blocks are an unavoidable consequence of mining in any proof-of-work system due to their decentralized nature and lack of coordination among miners. When this happens, miners who have invested resources into mining these blocks cannot collect rewards for them; instead they must move onto working on new valid blocks which can be added to the blockchain network.
