Constants

Role identifiers, policy-type identifiers, precompile addresses, and other fixed constants. See B20Constants and StdPrecompiles.

Precompile addresses

Fixed addresses of Base’s singleton precompiles. See StdPrecompiles.

Name	Value	Purpose
`B20_FACTORY_ADDRESS`	`0xB20f000000000000000000000000000000000000`	Deploys and looks up B-20 tokens; every asset and stablecoin instance is created through the `IB20Factory` at this address.
`POLICY_REGISTRY_ADDRESS`	`0x8453000000000000000000000000000000000002`	Stores allowlist/blocklist/composite policies and answers `isAuthorized` checks consulted by every policy scope (see Policies).
`ACTIVATION_REGISTRY_ADDRESS`	`0x8453000000000000000000000000000000000001`	Gates whether a B-20 variant or feature is live on a given chain; checked by the factory before it will create that variant.

Roles

Role identifiers checked via hasRole. See B20Constants and IB20. Hex values are keccak256 of the role name, verified with cast keccak "<NAME>" and cross-checked in chisel.

Name	Value	Purpose
`DEFAULT_ADMIN_ROLE`	`bytes32(0)`	Required to call `grantRole`, `revokeRole`, `setRoleAdmin`, `updatePolicy`, and `updateSupplyCap`.
`MINT_ROLE`	`keccak256("MINT_ROLE")` `0x154c00819833dac601ee5ddded6fda79d9d8b506b911b3dbd54cdb95fe6c3686`	Required to call `mint` and `mintWithMemo`.
`BURN_ROLE`	`keccak256("BURN_ROLE")` `0xe97b137254058bd94f28d2f3eb79e2d34074ffb488d042e3bc958e0a57d2fa22`	Required to call `burn` and `burnWithMemo`.
`BURN_BLOCKED_ROLE`	`keccak256("BURN_BLOCKED_ROLE")` `0x7408fdc0d31c7bcb349eab611f5d1168acd4303574993f8cdc98b1cd18c41cae`	Required to call the deprecated `burnBlocked`.
`SEIZE_ROLE`	`keccak256("SEIZE_ROLE")` `0x3469b8b0d89e9604f8510ed143f74a8336d22955d4f83e23bf53d9414e27f432`	Required to call `seizeWithMemo`.
`PAUSE_ROLE`	`keccak256("PAUSE_ROLE")` `0x139c2898040ef16910dc9f44dc697df79363da767d8bc92f2e310312b816e46d`	Required to call `pause`.
`UNPAUSE_ROLE`	`keccak256("UNPAUSE_ROLE")` `0x265b220c5a8891efdd9e1b1b7fa72f257bd5169f8d87e319cf3dad6ff52b94ae`	Required to call `unpause`.
`METADATA_ROLE`	`keccak256("METADATA_ROLE")` `0x6bd6b5318a46e5fff572d5e4258a20774aab40cc35ac7680654b9081fcc82f80`	Required to call `updateName`, `updateSymbol`, `updateContractURI`, and `updateExtraMetadata`.
`OPERATOR_ROLE`	`keccak256("OPERATOR_ROLE")` `0x97667070c54ef182b0f5858b034beac1b6f3089aa2d3188bb1e8929f4fa9b929`	B20Asset-only. Required to call `announce`, `updateUIMultiplier`, `cancelUIMultiplierUpdate`, and the deprecated `updateMultiplier`.

Policy types

Policy scopes consulted by the PolicyRegistry. See B20Constants and Policies. Hex values are keccak256 of the policy name, verified with cast keccak "<NAME>" and cross-checked in chisel.

Name	Value	Purpose
`TRANSFER_SENDER_POLICY`	`keccak256("TRANSFER_SENDER_POLICY")` `0xb81736c875ab819dd97f59f2a6542cfb731ad52b4ae15a6f24df2fb02b0327f5`	Consulted for `from` on `transfer` and `transferFrom`.
`TRANSFER_RECEIVER_POLICY`	`keccak256("TRANSFER_RECEIVER_POLICY")` `0x8a4b3fa2d8b921852bc0089c6ef0958aa6961897be36fd731330fe2cd23f8363`	Consulted for `to` on `transfer` and `transferFrom`.
`TRANSFER_EXECUTOR_POLICY`	`keccak256("TRANSFER_EXECUTOR_POLICY")` `0x10be5173aff2a44e748bd9acd8b19fe34689581398a9db7ba2fb671e786ff7d8`	Consulted for `msg.sender` on every transfer entrypoint (`transfer`, `transferFrom`, and memo’d variants).
`MINT_RECEIVER_POLICY`	`keccak256("MINT_RECEIVER_POLICY")` `0xa0d5ae037e66a09119acf080a1d807abb9b6d03b6b9130eb19f7c1e6bdb8ffc8`	Consulted for `to` on `mint`.
`SEIZE_EXEMPT_POLICY`	`keccak256("SEIZE_EXEMPT_POLICY")` `0xedb5da348cfb67af08746d3afd1be81034b50d5c8576f31aff688f39dfd540ed`	Consulted for `from` on `seizeWithMemo`; an authorized `from` is seize-exempt, so `from` is seizable only when unauthorized under this policy. Named `SEIZE_HOLDER_POLICY` before Cobalt.
`SEIZE_RECEIVER_POLICY`	`keccak256("SEIZE_RECEIVER_POLICY")` `0xbf15b19caf5c77422c038bc25f26b8b815c3a14f6d04c6616076b81bcfe07b3d`	Consulted for `to` on `seizeWithMemo`.

Feature and validation bounds

Bitmasks and inclusive bounds used for pause features and B20Asset creation validation. See B20Constants.

Name	Value	Purpose
`ALL_FEATURES_PAUSED`	`15` (`0b1111`)	Bitmask with all `PausableFeature` bits set (`TRANSFER \| MINT \| BURN \| SEIZE`).
`MIN_ASSET_DECIMALS`	`6`	Inclusive lower bound for `B20AssetCreateParams.decimals`; the floor most stablecoin-grade integrations expect.
`MAX_ASSET_DECIMALS`	`18`	Inclusive upper bound for `B20AssetCreateParams.decimals`; the ERC-20 community ceiling every common wallet/indexer renders correctly.
`MAX_SUPPLY_CAP`	`type(uint128).max`	Inclusive upper bound for the supply cap (and therefore `totalSupply`); doubles as the unbounded (“no cap”) sentinel.

Asset-variant precision constants

Fixed-point constants used by the multiplier/rebasing surface. See IB20Asset.

Name	Value	Purpose
`WAD_PRECISION`	`1e18`	Fixed-point precision used to scale `uiMultiplier`; `uiMultiplier`, `toUIAmount`, and `fromUIAmount` all divide/multiply by this.
`MAX_UI_MULTIPLIER`	`type(uint128).max`	Maximum multiplier the setters accept. It is the overflow guard enforced by `updateUIMultiplier` and the deprecated `updateMultiplier`. Exposed so callers can read the bound without triggering `InvalidMultiplier`.

Specifications

Reference

Node Operators

Security

Precompile addresses

Roles

Policy types

Feature and validation bounds

Asset-variant precision constants

​Precompile addresses

​Roles

​Policy types

​Feature and validation bounds

​Asset-variant precision constants

Precompile addresses

Roles

Policy types

Feature and validation bounds

Asset-variant precision constants