Soft Fork

A soft fork is a type of blockchain upgrade that is backward-compatible, meaning nodes that haven’t updated can still recognize and validate new blocks created under the updated rules. Unlike hard forks, which can split the network, a soft fork keeps the blockchain unified as long as a majority of mining or staking power enforces the new rules. Soft forks work by making previously valid actions invalid—for example, by tightening conditions on block or transaction formats—without expanding the protocol. This ensures older nodes remain part of the same chain, though they may not understand or enforce the new restrictions. Well-known examples include Bitcoin’s SegWit upgrade, which changed how transaction data is stored, and P2SH (Pay to Script Hash), which enabled more complex smart contract functionalities. The main advantage of soft forks is that they avoid network splits and don’t require users to migrate assets or use new coins. However, they are more limited in scope than hard forks, as they can only restrict rules rather than introduce entirely new functionalities.