PR Palais‑Royal Exchange Est. MDCCLXXXIV · PRX Open the book
I Paris, 1784 — the arcade that priced everything

A market existed here before the rules did.

The Duke of Orléans enclosed his garden in shops and discovered that royal ground sat outside police jurisdiction. Booksellers, gaming houses and unlicensed agioteurs moved into the arcades, and for forty years France's real price of government debt was set under this colonnade — four decades before the Bourse was given a building. Palais-Royal Exchange rebuilds that arrangement honestly: three venues with different economics, one router that proves which one deserved your order.

Quoted spread
bps
At the touch, Montpensier book
Routed liquidity
Across all three arcades
Median settlement
ms
Signature to final fill
Orders split
%
Touched more than one venue

Figures on this page are illustrative and deterministic — a reference market, not live data.

II The three galleries

Three arcades, three different ways to be filled.

Victor Louis built three galleries around the garden and rented every ground-floor bay to whoever paid. We kept the arrangement. Each venue below is a distinct market structure with its own failure mode — a book that runs thin, a pool that punishes size, a desk that simply stops. None of them wins every order, which is the entire reason the router exists.

III Le Perron — the open book

When the Bourse shut in 1795, trading moved to the steps.

Brokers without a licence — la coulisse — kept quoting rentes in the open air, and on several instruments they beat the official sixty on price. Their advantage was not secrecy but the opposite: everyone standing on the Perron could see the same size at the same moment. Every resting order here is readable before you trade against it.

Montpensier · Book LIV / USD
Mark price · 180 sessions
Mark price
Cumulative depth by distance from mid
Bid depth Ask depth
Tape Last 26
IV The router

Move the size. Watch the arcades trade places.

The router fills your order one increment at a time, always into whichever venue offers the cheapest next unit. When marginal prices equalise, the split is cost-minimal — that is the whole algorithm, and it is why the answer changes with size rather than with marketing. Below every result is the counterfactual: what the same order would have cost sent to one venue alone.

Order size · buy side
LIV
    Execution

    V Coulisse — the stated schedule

    One schedule. No privileged queue.

    The official brokers of the Ancien Régime held sixty hereditary seats and charged what the seat was worth. The coulisse undercut them because its pricing was published and identical for everyone who showed up. Fees here are stated in basis points, not derived from your order flow.

    Venue Structure Taker Maker Fill limit Fails by
    Read this before you trade anything. Every number on this page is generated from a seeded reference model so the site renders identically on every device. It is a demonstration of routing mechanics, not a live venue, not an offer, and not investment advice. Nothing here is a claim about future returns.
    VI PRX — the bay you own

    The Duke never sold the arcade. He leased the bays.

    Orléans kept the freehold and lived on ground rent, which is why the Palais-Royal outlasted every venue that tried to sell itself outright. PRX is a bay in that arcade: it earns a share of the rent the venues collect, and it lowers the rent you pay to trade through them. You never need it to place an order — the fee table above applies to everyone, staked or not.

    Where a basis point actually goes

    One skim, taken once, on filled size only. Follow it end to end — the loop closes back at the trader who paid it.

      VII The rent roll

      Paid from volume. Never from a printer.

      Every figure below is derived from the venue numbers on this page, not chosen to look attractive. Supply is fixed at 100,000,000 with no inflation, so the only way a holder earns is the skim on real routed flow — and the only way the float moves is down. If volume stops, the rent stops. That is the honest shape of it.

      Revenue split 0.8 bps of routed notional

        Bay ranks

        Stake more, pay less. The right-hand column is the part most token pages omit: the monthly volume at which the rebate alone repays the cost of capital tied up in the stake.

        Rank PRX staked Rebate Effective skim Rent / yr Rebate breaks even at Grant
        Who this is actually for

        Your volume Fees / yr Max rebate Beats cost of capital

        Distribution

        100,000,000 PRX, fixed. No private round priced beneath the public sale.

        Why a holder is better off

        Seven claims, each checkable against the numbers above.

        PRX does not exist yet, and this page is not a sale. The token layer shown here is a design, priced against an illustrative reference market so the mechanics can be inspected before anything is deployed. Figures are deterministic model output, not returns. Nothing on this page is an offer, a security, or investment advice.
        VIII The ledger

        How a garden became a market, and the market got a gate.

        Worth knowing because the ending repeats. An open venue attracts real price discovery, real price discovery attracts scale, and scale invites an authority to enclose it. The Palais-Royal was free until it was replaced by a building with a door.

        IX The charter

        Six commitments, written so you can catch us breaking them.

        Each clause below is falsifiable from public data. That is the only kind of promise worth publishing — if you cannot check it, it is decoration.

        The arcade never asked who you were.

        It asked whether you could pay the rent and quote a price. Custody stays in your account until a fill is signed, the book stays readable, and every route ships with the receipt that proves it.