Solana study finds wider spreads outside aggregators at five of six sampled pools

A September study found wider realized round-trip spreads for Solana trades routed outside aggregators at five of six major proprietary liquidity venues, suggesting that access to the same pool did not mean access to comparable trading terms.

The result puts the route into the center of the price comparison. A pool can settle trades on a public blockchain while a single operator controls its quotes. Comparing pool addresses alone therefore leaves out an important part of the transaction: how the order arrived.

The preprint by Ozan Solmaz, Lioba Heimbach and Jason Milionis, posted Sept. 29, examined proprietary automated market makers, or propAMMs, on Solana, Base and Monad. Its observations run from Sept. 1, 2025, through Aug. 31, 2026, with later starts for newer deployments. The Solana finding is a historical association between routing class and realized spreads, rather than a measurement of what every interface delivers today.

An aggregator searches across liquidity venues and can split an order among them. Jupiter is one such routing provider on Solana. A propAMM is the venue supplying liquidity: one operator provides inventory and can update prices directly, without waiting for a trade to change the pool's reserves.

The study compared aggregator and non-aggregator flow within the six largest measured Solana propAMMs for SOL/USDC. To estimate a realized round-trip spread, it paired consecutive fills on opposite sides of the same pool, within 25 slots and with trade sizes within a factor of two. There could be no intervening quote update from the operator, and both legs had to belong to the same routing class.

The researchers then compared the classes within cells defined by pool, day and trade-size bucket. That makes the test more informative than comparing unrelated venues or differently sized orders. It still pairs observed trades; the two fills need not be one customer's actual buy-and-sell journey.

Source: the study's Table 1. All spread figures are realized round-trip measurements. The matched premium is the median within-cell difference; the final column counts matched cells, not trades or trading volume.

One basis point is 0.01 percentage point. The distinction between the columns matters. Tessera's overall medians were 0.9 and 0.93 basis points, while its median matched premium was 0.1 basis points. The matched result comes from comparing the two classes inside each cell before summarizing those differences. Subtracting the displayed overall medians would answer a different question.

For the first five venues, non-aggregator spreads were wider in 68% to 83% of matched cells, with reported exact sign-test p-values below 0.001. ZeroFi went the other way on the matched median, with a small negative premium.

These are round-trip price gaps, not individual swap fees. Nor does the classification identify ordinary retail customers: non-aggregator flow can have different characteristics from aggregator flow. Matching pool, day and size reduces some differences between the groups, but it does not turn the comparison into a randomized test of what happens when the same person changes interfaces.

The economic rationale starts with stale prices. A passive pool can lose money when another trader acts on a market move before the pool's price catches up. PropAMM operators can send price updates without executing a swap, reducing that exposure when their updates arrive before incoming trades.