Optimism has launched a four-week temporary test on OP Mainnet, granting higher transaction sequencing priority to eligible OP token stakers. This extends the utility of OP from governance to on-chain block space allocation.
The test will be conducted in two phases.
This test, which began on May 26, marks the first deployment on an OP Stack chain of a staking-based transaction ordering system. Under the scheme, users must stake OP through Optimism’s PolicyEngineStaking contract to qualify for ordering priority.
The first phase lasts a maximum of one week. Wallets that stake at least 100,000 OP will receive a strict first-come, first-served priority. Staking more than this threshold provides no additional benefits.
The second phase, lasting up to three weeks, will switch to a weighting system based on staking size. The larger the stake, the higher the user’s effective priority fee multiplier, capped at 3x. Optimism states that this model uses a square root formula to ensure diminishing returns for large holders, rather than unlimited amplification.
No longer relying solely on gas bidding
This test replaces the common "priority gas auction" model. Previously, users primarily competed for earlier positioning by paying higher transaction fees; the new mechanism incorporates token staking into the ordering allocation.
This will directly impact on-chain participants who rely on execution speed, including market makers, arbitrage traders, MEV searchers, and other high-frequency trading entities. For these participants, changes in ordering can affect trade efficiency, execution costs, and strategy design.
Regular sorting will resume in four weeks.
From a protocol perspective, this also introduces new economic use cases for the OP token beyond just governance voting. Optimism is using this test to explore whether Layer 2 block space can be allocated through “staking + fees” rather than a single fee auction.
This mechanism may also spark discussions around fairness and centralization, as large token holders gain higher priority, leading some market participants to view it as a "pay-to-win" model tied to token holdings.
Optimism acknowledges the associated risks in its documentation and emphasizes that these sequencing guarantees are "best effort" and not absolute. The protocol also states that, after the four-week testing period, OP Mainnet will automatically revert to its standard transaction sequencing method.