Prediction Markets

Overview

evently Markets is the platform's core product — a LMSR-based prediction market where anyone can create or trade on outcomes using USDm (the MegaETH stablecoin).

You don't bet. You trade your conviction. Information becomes a financial asset — priced by the market, settled on-chain, with instant finality on MegaETH's ~1ms blocks.

Markets cover Crypto, Politics, Culture, World, Business, Entertainment, Science, and more. Many markets are sourced from Polymarket and display live Polymarket odds alongside evently's own prices for comparison.

Each outcome is represented as a tradable ERC-1155 share. One winning share redeems for exactly 1 USDm after market resolution — regardless of total volume or how many people traded the same way.

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Access

Markets are currently in invite-only early access. Users can gain access by:

• Invite code — redeem a code from an existing member

• Waitlist — submit your wallet at evently.market/markets

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Fee Structure

Fee	Recipient	Basis Points
Creator fee	Market creator	100 bps (1%)
Treasury fee	evently protocol treasury	100 bps (1%)
Resolver pool	Resolver / staking post-TGE	50 bps (0.5%)
Total		250 bps (2.5%)

Hard cap: 5% total via setFees(). Admin markets redirect the creator cut to the treasury.

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Pricing Mechanism — LMSR

Prices are determined by the Logarithmic Market Scoring Rule (LMSR), the same mechanism used by Polymarket. The LMSR guarantees that:

• Being correct always yields a profit (unlike parimutuel)

• Prices always sum to exactly 100%

• The market maker (AMM) is always solvent

Cost function: C(q) = b × ln( Σ exp(q[i] / b) )

Implied probability of option i: P(i) = exp(q[i]/b) / Σ exp(q[j]/b)

b = 200 USDm controls price sensitivity. At creation all options start at equal probability (e.g. 50/50 for binary markets).

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Order Matching — CLOB + AMM

Trades are routed through two layers:

1. CLOB (Central Limit Order Book): resting limit orders are matched first at price-time priority

2. LMSR AMM: any remaining budget is priced by the AMM as market maker of last resort

Buying: CLOB ask orders at or below your price are filled first. Remainder goes to the AMM.

Selling: instant sell to the AMM via sellToAMM(), or post a limit ask via placeOrder(SELL, ...).

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Market Categories

Category	Examples
Crypto	Price targets, DeFi TVL milestones, token launches
Politics	Elections, policy outcomes, geopolitical events
Culture	Memes, entertainment, viral trends
Pop Culture	TV, film, music awards
World	International events, macro
Business	M&A, earnings, IPOs
Science	Research outcomes, discoveries

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Market Lifecycle

Active → BettingClosed → Resolved → [Disputed] → Finalized
                                              |
                                        Cancelled / Slashed

1. Active

Shares can be bought and sold. Market is open until bettingDeadline.

2. BettingClosed

Deadline passed. No more trades. Waiting for resolution.

3. Resolved

Creator declares the winning option. A 24-hour dispute window opens.

4. Disputed

A whitelisted user can dispute the resolution by locking 50 USDm collateral. Admin adjudicates.

5. Finalized

No dispute raised (or dispute settled). Winners can redeem shares at 1 USDm each.

6. Cancelled / Slashed

• Cancelled: all holders get a pro-rata refund from the pool + subsidy

• Slashed: creator collateral forfeited to treasury; holders get pro-rata refund

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Market Creation

Community Markets (Whitelisted Users)

• Requires 50 USDm collateral + LMSR subsidy (b × ln(n) USDm)

• Collateral + subsidy returned on honest resolution

• Creator earns 1% of all volume accrued in creatorAccruedFees, claimable after finalization

• Must set clear resolutionCriteria

• 2 to 4 options per market; question max 300 characters; options max 100 characters each

Official Markets (Admin)

Created by the evently team — no collateral required. Displayed with an Official badge. Many are sourced from Polymarket with live odds displayed via the Polymarket CLOB API.

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Trading

placeOrder(marketId, optionIndex, side, quantity, pricePerShare, minFill)

• side: BUY or SELL

• pricePerShare: limit price in USDm (18 decimals), must be between 0 and 1

• minFill: slippage guard — reverts if total shares filled < this value

• BUY orders escrow USDm upfront; SELL orders escrow shares upfront

For instant AMM sells:

sellToAMM(marketId, optionIndex, shares, minUsdmOut)

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Redeeming Winnings

After finalization:

redeemWinnings(marketId)

Each winning share redeems for exactly 1 USDm. Solvency is guaranteed by the LMSR invariant: poolBalance + subsidyDeposited >= total winning shares.

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Polymarket Integration

Official markets import odds and volume data from Polymarket via the Gamma API and CLOB price history API. Polymarket odds are displayed for reference — evently prices are set independently by the LMSR AMM.

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Constants

Constant	Value
Creator collateral	50 USDm
Dispute collateral	50 USDm
Dispute window	24 hours
LMSR b parameter	200 USDm
Max options per market	4
Min options per market	2
Min trade	0.001 shares (1e15)
Max orders per book	200 per (market, option, side)