GlossaryAdvanced
Orphan Block
A validly mined block that ends up excluded from the main blockchain.
An orphan block is a block that was validly mined but ultimately isn't included in the chain the network settles on as the main, agreed-upon history — often because a competing block at the same height was accepted instead.
The miner of an orphaned block generally does not receive its block reward, even though the block itself met the network's validity rules.
Examples
- Two miners solving a block at nearly the same time can result in one of the two blocks becoming orphaned.
- An orphan block's transactions typically return to the mempool to be included in a later block.