> For the complete documentation index, see [llms.txt](https://docs.hypersurface.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hypersurface.io/overview/auctions.md).

# Auctions

Hypersurface holds the options it buys from sellers. Auctions sell that inventory back to the market. Anyone can take part, with no sign-up or whitelist.

The price opens high and falls over a few minutes. Take the whole auction or part of it, at the current price. Settlement is one transaction, in USDT0.

### Participating in an auction

Live auctions are at [app.hypersurface.io/auctions](https://app.hypersurface.io/auctions).

* Pick an auction and an amount.
* Set a maximum premium to cap what you pay.
* First come, first served. An auction closes once it is fully taken.

### What it means for option sellers

When an auction sells above the protocol's price, the difference goes back to whoever sold those options. See the [Rebate Ledger](/overview/rebate-ledger.md).

### Developer integration

Take auctions through the contracts directly, or through the app at [app.hypersurface.io/auctions](https://app.hypersurface.io/auctions). The [Integration Guide](/integration-guide.md) has the contract addresses and chain configuration.