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Update and rename batch-auctions.md to fair-combinatorial-auction.md #504

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Update and rename batch-auctions.md to fair-combinatorial-auction.md #504

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17 changes: 0 additions & 17 deletions docs/cow-protocol/concepts/introduction/batch-auctions.md
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18 changes: 18 additions & 0 deletions docs/cow-protocol/concepts/introduction/fair-combinatorial-auction.md
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# Fair Combinatorial Auction

CoW Protocol collects and aggregates [intents](./intents) off-chain and auctions them off to [solvers](./solvers). The auction is combinatorial because each solver can submit multiple bids. A solver can submit multiple bids on individual orders, in which case each "bid" represents the best price this solver can provide to an individual order. However, a solver can also submit "batched" bids, that is, bids on groups of orders.

The protocol filters our ``unfair'' batched bids, which are those delivering less to an order than some available "non-batched" bids. It then selects the combination of winning bids that maximizes the surplus received by the orders that are part of the auction (subject to some computational constraints due to the combinatorial nature of the problem).

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@coderabbitai coderabbitai bot Jun 2, 2025 •
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⚠️ Potential issue

Fix typo in text (“filters our” → “filters out”).

The sentence currently reads “The protocol filters our unfair batched bids…”. It should be:

The protocol filters out `unfair` batched bids…
🤖 Prompt for AI Agents 
In docs/cow-protocol/concepts/introduction/fair-combinatorial-auction.md around
lines 9 to 10, fix the typo by changing "filters our" to "filters out" so the
sentence correctly reads "The protocol filters out `unfair` batched bids…".

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yep, this needs correcting.

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@pretf00d Thanks for confirming! I'll plan the fix for this typo.

Task: Fix typo in fair-combinatorial-auction.md

  • Change "filters our" to "filters out" on line 9

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A summary of the edits CodeRabbit can apply:

Fix typo in fair-combinatorial-auction.md by changing "filters our" to "filters out" on line 9.

A plan of each step that CodeRabbit will take in order to execute the edits for each file (with inline rough draft snippets):

✏️ docs/cow-protocol/concepts/introduction/fair-combinatorial-auction.md

Locate line 9 in the file which currently reads: "The protocol filters our ``unfair'' batched bids, which are those delivering less to an order than some available "non-batched" bids. It then selects the combination of winning bids that maximizes the surplus received by the orders that are part of the auction (subject to some computational constraints due to the combinatorial nature of the problem)."

Replace the word "our" with "out" in the phrase "filters our" so it becomes "filters out". The corrected line should read: "The protocol filters out ``unfair'' batched bids, which are those delivering less to an order than some available "non-batched" bids. It then selects the combination of winning bids that maximizes the surplus received by the orders that are part of the auction (subject to some computational constraints due to the combinatorial nature of the problem)."

Verify that only the single word "our" has been changed to "out" and that all other text, punctuation, and formatting remains exactly the same.

  • ✅ Create PR with these edits
  • 📌 Create commit in current branch
  • 📋 Get copyable edits

![The Auctions](/img/concepts/batch-auctions.png)

The fair combinatorial auction provide several benefits:

- [**MEV Protection**](../benefits/mev-protection): Batch auctions allow for Uniform Clearing Prices (UCPs), where an asset that appears multiple times across orders in the same batch settles for a consistent price.
This makes transaction order irrelevant within the block, undermining the ability for MEV bots to extract value.
- **[Coincidence of Wants](../how-it-works/coincidence-of-wants)**: When multiple orders trade the same assets within a batch, there may be an opportunity for a peer-to-peer swap that doesn't tap on-chain liquidity, which a solver could exploit by submitting a batched bid.
- **Fairness**: Ensuring that each order receives as much as it would have received had that order been auctioned off alone.
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🛠️ Refactor suggestion

Align bullet content with “Fair Combinatorial Auction”.

The benefits still reference “Batch auctions” and “within a batch,” which conflicts with the new mechanism name. Please update the text to refer to “combinatorial auctions” (or “fair combinatorial auction”) consistently. For example:

- - [**MEV Protection**](../benefits/mev-protection): Batch auctions allow for Uniform Clearing Prices …
+ - [**MEV Protection**](../benefits/mev-protection): Combinatorial auctions allow for Uniform Clearing Prices …

- - **[Coincidence of Wants](../how-it-works/coincidence-of-wants)**: When multiple orders trade the same assets within a batch, …
+ - **[Coincidence of Wants](../how-it-works/coincidence-of-wants)**: When multiple orders trade the same assets in the combinatorial auction, …

- - **Fairness**: Ensuring that each order receives as much as it would have received had that order been auctioned off alone.
+ - **Fairness**: Ensuring that each order receives at least what it would have secured if auctioned individually.
📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change
- [**MEV Protection**](../benefits/mev-protection): Batch auctions allow for Uniform Clearing Prices (UCPs), where an asset that appears multiple times across orders in the same batch settles for a consistent price.
This makes transaction order irrelevant within the block, undermining the ability for MEV bots to extract value.
- **[Coincidence of Wants](../how-it-works/coincidence-of-wants)**: When multiple orders trade the same assets within a batch, there may be an opportunity for a peer-to-peer swap that doesn't tap on-chain liquidity, which a solver could exploit by submitting a batched bid.
- **Fairness**: Ensuring that each order receives as much as it would have received had that order been auctioned off alone.
- [**MEV Protection**](../benefits/mev-protection): Combinatorial auctions allow for Uniform Clearing Prices (UCPs), where an asset that appears multiple times across orders in the same batch settles for a consistent price.
This makes transaction order irrelevant within the block, undermining the ability for MEV bots to extract value.
- **[Coincidence of Wants](../how-it-works/coincidence-of-wants)**: When multiple orders trade the same assets in the combinatorial auction, there may be an opportunity for a peer-to-peer swap that doesn't tap on-chain liquidity, which a solver could exploit by submitting a batched bid.
- **Fairness**: Ensuring that each order receives at least what it would have secured if auctioned individually.
🤖 Prompt for AI Agents 
In docs/cow-protocol/concepts/introduction/fair-combinatorial-auction.md around
lines 15 to 18, the bullet points incorrectly refer to "Batch auctions" and
"within a batch," which conflicts with the new mechanism name "Fair
Combinatorial Auction." Update all mentions of "Batch auctions" and related
phrases to "Combinatorial auctions" or "Fair Combinatorial Auction" to maintain
consistent terminology throughout the section.