> ## Documentation Index
> Fetch the complete documentation index at: https://sec-edgar-mcp.amorelli.tech/llms.txt
> Use this file to discover all available pages before exploring further.

# Lookup Company CIK

> Convert ticker symbols to CIK numbers

## Overview

The `lookup_company_cik` tool converts company ticker symbols to CIK (Central Index Key) numbers for more reliable API performance.

## Parameters

* `ticker` (string): Company ticker symbol (e.g., "AAPL")

## Example Usage

```text theme={null}
"What is Apple's CIK number?"
```

## Response Format

```json theme={null}
{
  "success": true,
  "cik": "0000320193",
  "ticker": "AAPL",
  "suggestion": "Use CIK '0000320193' instead of ticker 'AAPL' for more reliable and faster API calls"
}
```