# Modifying Builder Subnets

## Transferring Ownership of a Subnet

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V1 Subnets cannot be transferred from one address to another.
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## Upgrading Subnets

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Subnets are not automatically upgraded to the next version of the Builder Contract. When a new Builder Contract is released, Subnets are required to register a new Subnet.
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## Editing Subnet Configurations

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Subnet data and parameters are immutable once the Start Date is passed. If you need to change immutable subnet configurations you will need to register a new Subnet.
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