# Purchasing a Core Dataset

Some evals offer a Core Dataset for purchase in addition to per-run evaluations. The Core Dataset contains the full bundle of tasks, answer keys, grading criteria, reference files, and any supplementary expert materials.

## Why Purchase a Core Dataset?

Core Datasets are useful for:

* Analyzing which specific tasks your model failed and why
* Using the answer keys and rationales for reinforcement learning
* Fine-tuning models on expert-authored domain data
* Auditing the eval methodology

## How to Purchase

On the eval's detail page, the Core Dataset section in the right panel shows the price and minimum bid (if bidding is enabled).

* Buy Now: click "Buy Now" and complete checkout at the listed price
* Place Bid: click "Place Bid" to submit a sealed bid at or above the minimum. Bids are binding and cannot be cancelled. The seller reviews bids and can accept or reject them.

Payment is via Stripe or USDC on Base Chain, the same as for eval runs and dataset purchases.

After purchase, the Core Dataset is available for download in the Data Studio under Purchases & Downloads.
