> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# getMasterchainBlockSignatures | TON v2

> The getMasterchainBlockSignatures method retrieves the signatures of a specific masterchain block in the TON blockchain. On TON v2.

The `getMasterchainBlockSignatures` method retrieves the signatures of a specific masterchain block in the TON blockchain. This method is crucial for verifying the authenticity and consensus of masterchain blocks.

<Note>
  **TON billing: full or archive by block age**

  This method is billed as archive (2 RUs) when the requested block is 128 or more seqno behind the tip, and full (1 RU) otherwise. See [Request units — TON method scope](/docs/request-units#ton-method-scope).
</Note>

## Parameters

* `seqno` (integer, required) — The sequence number of the masterchain block for which to retrieve signatures. Example: `39064874`.

## JSON-RPC example

```shell Shell theme={"system"}
curl -X POST \
  'https://ton-mainnet.core.chainstack.com/f2a2411bce1e54a2658f2710cd7969c3/api/v2/jsonRPC' \
  -H 'Content-Type: application/json' \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "getMasterchainBlockSignatures",
    "params": {
      "seqno": 39064874
    }
  }'
```

## Response

* `signatures` (array of objects) — An array of signature objects, each containing:
  * `node_id` (string) — The ID of the validator node that provided the signature.
  * `r` (string) — The 'r' component of the signature.
  * `s` (string) — The 's' component of the signature.
* `validator_set_hash` (string) — The hash of the validator set that signed this block.
* `catchain_seqno` (integer) — The sequence number in the catchain (consensus protocol).

## Use case

A possible use case for the `getMasterchainBlockSignatures` method in TON is for applications or services that need to verify the authenticity and consensus of masterchain blocks. This method can be used to:

1. Implement custom block validation logic in light clients or explorers.
2. Verify the consensus reached for a specific block by checking the signatures.
3. Analyze validator participation and performance in block signing.
4. Provide transparency and auditability for critical blockchain operations.


## OpenAPI

````yaml openapi/ton_node_api/v2/getMasterchainBlockSignatures.json GET /getMasterchainBlockSignatures
openapi: 3.0.0
info:
  title: getMasterchainBlockSignatures example
  version: 1.0.0
  description: >-
    This is an API example for getMasterchainBlockSignatures, a method to
    retrieve the signatures of a specific masterchain block.
servers:
  - url: >-
      https://ton-mainnet.core.chainstack.com/f2a2411bce1e54a2658f2710cd7969c3/api/v2
security: []
paths:
  /getMasterchainBlockSignatures:
    get:
      tags:
        - TON Operations
      summary: getMasterchainBlockSignatures
      operationId: getMasterchainBlockSignatures
      parameters:
        - name: seqno
          in: query
          required: true
          description: The sequence number of the masterchain block
          schema:
            type: integer
            default: 39064874
          example: 39064874
      responses:
        '200':
          description: Signatures of the specified masterchain block
          content:
            application/json:
              schema:
                type: object
                properties:
                  signatures:
                    type: array
                    items:
                      type: object
                      properties:
                        node_id:
                          type: string
                          description: The ID of the validator node
                        r:
                          type: string
                          description: The 'r' component of the signature
                        s:
                          type: string
                          description: The 's' component of the signature
                  validator_set_hash:
                    type: string
                    description: The hash of the validator set
                  catchain_seqno:
                    type: integer
                    description: The sequence number in the catchain

````