# Do Ahead-of-Time Auctions Work?

**URL:** https://collective.flashbots.net/t/do-ahead-of-time-auctions-work/5389
**Category:** Research
**Created:** [November 25, 2025, 3:23pm UTC](https://collective.flashbots.net/t/do-ahead-of-time-auctions-work/5389 "2025-11-25T15:23:17Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Christoph](https://collective.flashbots.net/letter_avatar_proxy/v4/letter/c/eb8c5e/32.png) [@Christoph](https://collective.flashbots.net/u/Christoph)
#### Post date: [November 25, 2025, 3:23pm UTC](https://collective.flashbots.net/t/do-ahead-of-time-auctions-work/5389/1 "2025-11-25T15:23:17Z")

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We looked into Arbitrum’s TimeBoost auction in this new short paper [[2511.18328] TimeBoost: Do Ahead-of-Time Auctions Work?](https://arxiv.org/abs/2511.18328)  
TimeBoost runs an “express lane” auction every minute and the winner of the auction has their transactions “time-boosted” by 200 ms during the next minute.

Evaluating the performance of the TimeBoost tx policy is an interesting exercise in itself, but I think the results can be insightful beyond this particular context: a main finding of the empirical analysis is that bids for the fast-lane are a reasonably good predictor of longer time average arbitrage profits, but a very noisy predictor of one minute profits. Thus, auctioning rights for earlier transaction execution ahead-of-time instead of just-in-time arguably lowers auction efficiency and revenue.  
This might also cast some doubt on the idea of AOT slot auctions as a suitable market structure for block building in Ethereum.

As always, comments are very welcome.