What is a soft fork?

What Is a Soft Fork?

A soft fork is a change to the blockchain rules that makes previously valid blocks or transactions invalid under the new rules. Old nodes still see the new blocks as valid (they are a subset of what they accept), so the network stays on one chain. There is no split into two coins. Upgraded nodes enforce the new rules; old nodes follow along.

Examples

Bitcoin has had soft forks that added new features (e.g. SegWit) while keeping the chain unified. Soft forks require broad agreement so that most miners or validators upgrade. If too many stay on the old rules, the network could split anyway.

For Users

As a user, you usually just need to use updated wallet or exchange software if needed. Your coins are on one chain. Soft forks are common for upgrades and do not typically create a second asset you need to claim or move.