# Emit INVALID_FORMAT for malformed VAT

**Use case:** 

Demonstrate format rejection for a malformed VAT input before calling VIES, emitting an INVALID_FORMAT diagnostic row. Export JSON/CSV via the Apify API.

## Input

```json
{
  "vatNumbers": [
    "NOTAVAT"
  ],
  "maxItems": 5,
  "proxyType": "none",
  "proxyConfiguration": {
    "useApifyProxy": false
  }
}
```

## Output

```json
{
  "inputVat": {
    "label": "inputVat",
    "format": "string"
  },
  "countryCode": {
    "label": "countryCode",
    "format": "string"
  },
  "vatNumber": {
    "label": "vatNumber",
    "format": "string"
  },
  "isValid": {
    "label": "isValid",
    "format": "string"
  },
  "requestDate": {
    "label": "requestDate",
    "format": "string"
  },
  "userError": {
    "label": "userError",
    "format": "string"
  },
  "name": {
    "label": "name",
    "format": "string"
  },
  "address": {
    "label": "address",
    "format": "string"
  },
  "consultationNumber": {
    "label": "consultationNumber",
    "format": "string"
  },
  "sourceUrl": {
    "label": "sourceUrl",
    "format": "string"
  },
  "scrapedAt": {
    "label": "scrapedAt",
    "format": "string"
  }
}
```

## About this Actor

This example demonstrates how to use [EU VIES VAT Number Validator](https://apify.com/bakos_bence/vies-vat-validator.md) with a specific input configuration. Visit the [Actor detail page](https://apify.com/bakos_bence/vies-vat-validator.md) to learn more, explore other use cases, and run it yourself.


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For full API examples (JavaScript, Python, CLI, MCP, OpenAPI), see this Task's Actor page: https://apify.com/bakos_bence/vies-vat-validator.md

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).