Forks & BTC1
The word “fork” covers several different changes. Follow the rule change and the chain history to see what a familiar name actually means.
By Bitcoin Field Guide. Published and updated .
Start with the rules
A hard fork can create two lasting chains if people keep validating both rule sets. A rule change alone does not guarantee a new asset.
New rules are stricter. Blocks that follow them still satisfy the older rules. SegWit and Taproot are Bitcoin soft-fork upgrades. They did not create separate coins named after the upgrades.
A changed rule set can accept blocks that older software rejects. A lasting chain split needs participants to keep the distinct networks running.
Developers copy software and develop it separately. That does not establish a split from Bitcoin's live transaction history. Litecoin's repository is an example of a Bitcoin code fork.
A selected chain map
Chain history shows which networks share transactions before a split. These historical examples do not establish current network activity, security or operation.
BTC continues on its own chain.
Direct BTC split in August 2017.
Direct BTC split in October 2017.
A branch from BCH in November 2018.
A branch from BCH in November 2020.
A lasting split with different block-size rules. Bitcoin Cash and BTC share the transaction history before their split.
Bitcoin Cash NodeThe project used Bitcoin history at block 491,406 and pursued a different set of mining rules.
Bitcoin Gold recordIts code repository describes a separate chain branching at Bitcoin block 495,866.
Project repositoryIts repository records a fork at block 505,888 and describes hybrid consensus and atomic-swap goals. These are project descriptions.
Project repositoryThis chain came from a Bitcoin Cash split. Its ancestry passes through BCH, rather than a direct split from BTC in 2018.
Protocol historyBitcoin ABC records a separation from Bitcoin Cash on November 15, 2020. The resulting BCHA project later became eCash, using the XEC unit.
Bitcoin ABC accountPut the name in context
Bitcoin Genesis 1 (BTC1) is a separate cryptocurrency project described in Bitcoin Ecosystem materials. It is not the bitcoin asset (BTC) or Bitcoin Core software.
The project's materials describe reserve, governance and utility ambitions, proof of work and an annual supply figure. Those statements are project claims. This guide does not independently verify them.
The reviewed reference material does not establish a specific shared-history fork point with Bitcoin. BTC1 is therefore not treated here as a verified direct BTC chain split.
Similar naming does not show shared security, transaction history or endorsement by Bitcoin Core.
Read the project's own descriptionWhat would count as evidence?
Project claims need inspectable code and records of network activity, supply, governance and custody.
Look for working network records, a public explorer and software that can be inspected. A description alone does not establish current operation.
Compare published issuance and allocation rules with observable network records. The claims and the records need to agree.
Identify who controls changes and custody, and look for supporting records. Consider technical, market, liquidity and custody risks separately.
Fork and BTC1 facts follow the supplied Bitcoin Compass reference pages, reviewed October 2, 2026. Project descriptions are attributed, not independently verified. Current status may differ.
Before any claim
Keep your Bitcoin recovery phrase out of unfamiliar tools, even when they promise access to another coin.
Fork eligibility depends on the project, the relevant snapshot, your keys and any custodian rules. A claimed entitlement is never a reason to enter your Bitcoin recovery words into an unfamiliar website.
A shared history does not establish equal security. The fork and BTC1 questions below explain the distinctions and the evidence to check.
Answers for the field
Forks change rules or code; a familiar name alone does not establish a shared Bitcoin history.
A soft fork tightens rules so that blocks following the new rules still satisfy the old rules. A hard fork can accept blocks older software rejects. A lasting chain split requires participants to keep both networks running. Copying software is a code fork and does not by itself establish shared live transaction history.
No. Eligibility depends on the project's design, the relevant snapshot and the keys you controlled, or your custodian's rules. Never put a Bitcoin recovery phrase into an unfamiliar claim website.
No. BTC1 means Bitcoin Genesis 1, a separate cryptocurrency project described in Bitcoin Ecosystem materials. BTC is the asset native to Bitcoin, while Bitcoin Core is software that validates Bitcoin blocks and transactions. The BTC1 name does not establish Bitcoin Core endorsement or shared security with the Bitcoin network.
No. A shared transaction history or copied code does not imply equivalent security, participation or value.
No. Reserve, governance, utility, proof-of-work and supply descriptions are attributed to the project's published materials. This guide does not independently verify those claims. Check inspectable software, network records, issuance and allocation data, governance and custody records, and independent analysis before relying on a project description.