Event signature · Stablecoins and issued tokens

Issue (USDT) event signature and topic0

The topic0 of the Issue (USDT) event is 0xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176a, the keccak-256 hash of Issue(uint256); none of its arguments are indexed. New tokens issued to the owner (Tether).

Anatomy of a Issue (USDT) log

Topics

topic00xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176akeccak256("Issue(uint256)")

Data

dataamount (uint256)ABI-encoded, decoded with the ABI

Parameters

Arguments and where they sit in the log

Indexed arguments travel as topics and can be filtered cheaply; the others are ABI-encoded together in the data.

Name	Type	In the log
amount	uint256	data

Solidity declaration

event Issue(uint256 amount);

Canonical signature

Issue(uint256)

topic0

0xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176a

Ready-made alerts

Get an alert on Issue

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Ready-made rule · Tether (USDT)USDT mints and burns

Ready-made rule · Tether (USDT)Alert on every Issue

Ready-made rule · Any contractAlert on Issue from a contract you pick

Who emits it

Contracts we list that emit Issue

Any other contract with the same signature emits a log with the same topic0.

Tether (USDT)

0xdac17f958d2ee523a2206206994597c13d831ec7

Tracker: USDT (Tether)

Code

Read Issue logs in code

The same filter in viem, ethers and plain JSON-RPC, and the Solidity that emits it. The address is Tether (USDT), a contract we list that emits it.

viem

import { createPublicClient, http, parseAbiItem } from "viem"
import { mainnet } from "viem/chains"

const client = createPublicClient({ chain: mainnet, transport: http() })

const logs = await client.getLogs({
  address: "0xdac17f958d2ee523a2206206994597c13d831ec7",
  event: parseAbiItem("event Issue(uint256 amount)"),
  fromBlock: "latest",
})

for (const log of logs) console.log(log.args) // { amount }

ethers v6

import { Interface, JsonRpcProvider } from "ethers"

const provider = new JsonRpcProvider(process.env.RPC_URL)
const iface = new Interface(["event Issue(uint256 amount)"])

const logs = await provider.getLogs({
  address: "0xdac17f958d2ee523a2206206994597c13d831ec7",
  topics: [iface.getEvent("Issue")!.topicHash],
})

for (const log of logs) console.log(iface.parseLog(log)?.args)

JSON-RPC (eth_getLogs)

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_getLogs",
  "params": [
    {
      "address": "0xdac17f958d2ee523a2206206994597c13d831ec7",
      "topics": [
        "0xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176a"
      ],
      "fromBlock": "latest"
    }
  ]
}

Solidity

event Issue(uint256 amount);

// inside a function:
emit Issue(amount);

Example

An example Issue log, encoded and decoded

Placeholder values, not a real transaction: how each argument is stored in the topics and the data, and what decoding gives back.

Encoded (as the node returns it)

topic0keccak256("Issue(uint256)")0xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176a
data0x00000000000000000000000000000000000000000000000000000000000003e8

Decoded with the ABI

amountuint2561000

FAQ

Frequently asked questions

What is the topic0 of the Issue (USDT) event?

0xcb8241adb0c3fdb35b70c24ce35c5eb0c17af7431c99f827d44a445ca624176a: the keccak-256 hash of Issue(uint256).

Which Issue (USDT) arguments are indexed?

None: amount is ABI-encoded in the log's data, so a log can only be filtered by address and topic0.

How do I get an alert when a contract emits Issue (USDT)?

Open one of the ready-made rules on this page, or add any contract and pick Issue (USDT) from the event list. Conditions can be set on its arguments, and each alert names the contract and links to the transaction.

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