# UNLModify

[[Source]](https://github.com/XRPLF/rippled/blob/master/src/xrpld/app/tx/detail/Change.cpp)

A `UNLModify` [pseudo-transaction](/es-es/docs/references/protocol/transactions/pseudo-transaction-types) marks a change to the [Negative UNL](/es-es/docs/concepts/consensus-protocol/negative-unl), indicating that a trusted validator has gone offline or come back online.

You cannot send a pseudo-transaction, but you may find one when processing ledgers.

NegativeUNL
## Example  JSON


```json
{
  "Account": "",
  "Fee": "0",
  "LedgerSequence": 1600000,
  "Sequence": 0,
  "SigningPubKey": "",
  "TransactionType": "UNLModify",
  "UNLModifyDisabling": 1,
  "UNLModifyValidator": "ED6629D456285AE3613B285F65BBFF168D695BA3921F309949AFCD2CA7AFEC16FE",
}
```

##  Fields

In addition to the [common fields](/es-es/docs/references/protocol/transactions/pseudo-transaction-types),  pseudo-transactions use the following fields:

| Name | JSON Type | [Internal Type](/docs/references/protocol/binary-format) | Description |
|  --- | --- | --- | --- |
| `TransactionType` | String | UInt16 | The value `0x0066`, mapped to the string `UNLModify`, indicates that this object is an `UNLModify` pseudo-transaction. |
| `LedgerSequence` | Number | UInt32 | The [ledger index](/docs/references/protocol/data-types/basic-data-types#ledger-index) where this pseudo-transaction appears. This distinguishes the pseudo-transaction from other occurrences of the same change. |
| `UNLModifyDisabling` | Number | UInt8 | If `1`, this change represents adding a validator to the Negative UNL. If `0`, this change represents removing a validator from the Negative UNL. (No other values are allowed.) |
| `UNLModifyValidator` | String | Blob | The validator to add or remove, as identified by its master public key. |