Yes and No Shares
Definition
Yes and no shares are the two sides of a binary event contract. A yes share pays $1 if the event occurs and nothing otherwise; a no share pays $1 if it does not occur. Polymarket describes resolution simply: 'holders of winning shares receive $1 per share, losing shares become worthless, and trading of shares is no longer possible.' Buying no is economically similar to selling yes.
Why it matters
A yes or no share is a fully funded bet with a capped gain and a capped loss. The price paid sets both: buying at 90 cents risks 90 cents to make 10, before fees. Investors should look at the ask they will actually pay, the fee at that price, and the payout ratio, not only at the displayed probability.
Common misconceptions
- •A cheap share is not a better deal; a 10-cent yes loses its cost nine times out of ten if the price is right.
- •No is not a short sale with unlimited risk; it is a fully funded position paying $1 if the event does not occur.
- •Yes plus no costs slightly more than $1 at the asks, because of spreads.
- •The label is only a starting point. Investor outcomes usually depend on the governing documents, cash-flow priority, valuation policy, disclosure quality, and manager discretion surrounding the term, not just the shorthand definition used in marketing materials.
Technical details
Payoff of one share
Buy yes at $0.70: win $0.30 if yes, lose $0.70 if no, before fees.
Buy no at $0.30: win $0.70 if no, lose $0.30 if yes, before fees.
Hold one of each: receive $1 whatever happens, so the pair should cost about $1.
How investors apply the term
Investors usually apply this term by tying the definition back to the controlling documents and then asking which cash flows, rights, restrictions, or valuation assumptions it changes. A useful review looks at the term alongside fees, leverage, liquidity, reporting frequency, and manager discretion rather than treating it as a standalone concept.
The practical diligence test is simple: identify who benefits if the assumption is wrong, who has control when conditions change, and what evidence the investor receives after closing. Terms that cannot be reconciled to documents, cash movements, and monitoring data should be treated as marketing shorthand until proven otherwise.
Frequently asked questions
- What do I buy when I purchase a Yes or No contract?
- A claim to $1 if your side wins, paid for at the current price. In the CFTC's rain example, yes costs 70 cents and no costs 30 cents. If it rains, each yes pays $1 and each no pays nothing; if it does not, the reverse.
- Why do the yes and no prices add up to about $1?
- Because one yes and one no together always pay exactly $1. If the two cost noticeably less than $1, a trader could buy both and lock in a gain; if more, a trader could sell both. In practice the asks sum to slightly more than $1 because of the bid-ask spread, and fees add to the cost.
- How much can I lose?
- What you paid, plus fees, for a fully collateralized contract. Kalshi's disclosure says members 'risk losing their cost to enter any transaction, including fees.' Kalshi's event contracts are fully collateralized at its clearinghouse, so the purchase price is the maximum loss; leveraged products are different.
- Do I have to wait for settlement?
- No. The CFTC notes that customers 'can trade in and out of their position prior to settlement at the current market price to lock in gains or limit losses.' Selling early realizes the current bid, less any fee, rather than $1 or $0.