# Launch holders · Elysium API · Femtos

> Every holder of a launched token, tagged dev or early buyer, with concentration.

- Base URL: `https://api.femtos.xyz/v1` (REST) · `wss://api.femtos.xyz/v1/ws` (WebSocket) · MCP: `https://api.femtos.xyz/mcp`
- Auth: `Authorization: Bearer $FEMTOS_KEY`. Free key: https://femtos.xyz/accounts/ (browser), or with
  no browser: `GET https://femtos.xyz/accounts/agent/challenge`, solve its proof of work, then `POST https://femtos.xyz/accounts/agent/signup`
  (https://femtos.xyz/agents.md#agent-onboarding)
- Decimals are exact strings, times Unix milliseconds, addresses lowercase `0x`
- Whole API in one file: https://femtos.xyz/agents.md · OpenAPI: https://api.femtos.xyz/v1/openapi.json · Index: https://femtos.xyz/llms.txt
- Page with live calls: https://femtos.xyz/elysium/launch-holders

## Launch holders — GET `/v1/launches/{token}/holders`

Every holder of a launched token, tagged dev or early buyer, with concentration.

| Param | In | Example or values |
|---|---|---|
| `token` | path | `<token>` |
| `limit` | query | `20` |
| `offset` | query | (optional) |

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/launches/<token>/holders?limit=20"
```

| Field | Type | Meaning |
|---|---|---|
| `totalHolders` | int | positive balances, system excluded |
| `concentration` | object | top 1 / 10 / 20 / 50 shares, HHI, dev, flagged early buyers, held share |
| `system` | object | PancakeSwap Infinity vault and PoolManager, Ascend treasuries: count, share |
| `holders[]` | object | {rank, address, amount, shareOfSupply, firstSeenAt, lastActiveAt, tag?, flags?} |
| `next` | int \| null | offset of the next page |

## Related (Holders & signals)

- [Holders](https://femtos.xyz/elysium/holders.md): Current balances of a token, largest first, with concentration.
- [Launch detail & signals](https://femtos.xyz/elysium/signals.md): Metrics, dev wallet, early buyers and risk signals of one launch.

All Elysium endpoints: https://femtos.xyz/elysium.md