> For the complete documentation index, see [llms.txt](https://hyperliquid-ohlc.gitbook.io/api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hyperliquid-ohlc.gitbook.io/api-docs/websocket-api/fills.md).

# Fills

Once websocket connection is established, you can initiate a fills data feed by sending a subscription message with the following format

```
{
    "method": "subscribe",
    "subscription": {
        "event_type": "fills",
        "coin": "<coin>",  // optional filter
        "user": "<address>",  // optional filter
        "builder": "<builder address>"  // optional filter
    }
}
```