How a sale works, end to end

One lot, followed from the moment a consignor ships it to the moment they are paid, naming every system it passes through, every document that binds it, and every point at which value moves.

This page is the map. It states each step once and links to the chapter that documents it properly, so a reader can find out where a thing happens before deciding how much they need to know about it.

Before the sale#

1. The house

   Intake and inspection. A consignor submits a card through consignment. The specialist desk inspects the holder against tamper and counterfeit markers, confirms the certificate against the grading company's population report, and photographs the slab. A card that fails inspection is returned; the house may decline any consignment, and may withdraw a lot before it closes for doubts about authenticity or title.

2. The house

   Into the vault. The desk records the card arriving, and then verifies it: a named member of staff checks the object against what was submitted and puts it away. The route that turns a submission into a live lot refuses one with no verified vault asset behind it, so nothing is offered for sale before the house physically holds it. A card already in the vault skips the post entirely and is claimed for the submission where it sits. The vault.

3. The house

   Cataloguing. The lot gets its heading line (set, card, grade, certificate number), an estimate range, and an opening price. A confidential reserve may be set, never above the low estimate. Seller commission is 0%; the house earns on the buyer-side fee instead.

4. The house

   The rules are frozen. The lot is attached to an auction, and that auction points at an immutable auction_rules row holding the increment ladder, the fee tranches, the extension window and the extension cap in force. Those numbers are read from the frozen snapshot for the rest of the lot's life, so a deploy cannot change the economics under a live lot. Auction engine.

Registration and funding#

1. The bidder

   Registration. An email address verified by a six-digit code, or a wallet proved by signature. Watching is free; bidding requires an account. Registration screens the account through the configured compliance provider and stamps the result. Screening.

2. The bidder

   Deposit. Where the escrow is enabled, the bidder signs a deposit, or a single depositWithPermit, from their own wallet into the BidEscrow contract. The tokens leave their wallet and sit in the contract, credited to their address. Minthouse signs nothing here and cannot initiate it. How the bid escrow works.

Bidding#

1. The bidder

   A bid is placed. Either a sealed maximum: the most the bidder will pay, with the house bidding on their behalf at the lowest winning price, or an exact amount. Both are irrevocable offers. Bids can be raised, never lowered or withdrawn. Bidding mechanics.

2. The engine

   Resolution. The engine compares the challenger's maximum against the standing leader's, applies the increment ladder from the frozen rules, and decides the new price and the new leader in one database transaction. Equal maximums break for the earlier bid. The algorithm.

3. The engine

   The ruling is recorded and signed. The decision is appended to a hash-linked event chain, each event carrying the hash of the one before it, and a receipt is minted binding that chain position, the price, the outcome and the rules version. The bidder can fetch their receipt; anyone else gets the same ruling with the account masked. Receipts and the event chain.

4. The settler

   The lock follows the lead. If the escrow is enabled and the bidder now leads, the house's settler key calls lock(bidder, lot, amount), locking the standing maximum plus the auction house fee on it against that lot. If a previous leader was displaced, their lock is released. Both operations are enqueued in the same database transaction as the bid and drained by a worker. Locking.

5. Anyone

   The lock is public. The lock amount equals the sealed maximum plus its fee, so an observer can infer the maximum from the chain. This is a deliberate trade and the house states it rather than denying it: a lock at the public price instead would leave promised proxy exposure withdrawable, and a winning bid the house cannot collect is worse than a maximum an observer can read. What is revealed.

The close#

1. The engine

   Extended bidding. A bid inside the final five minutes moves the close to five minutes after that bid, anchored to the bid and never stacked onto the old close, capped at 30 minutes of total extension per lot. Lots close independently and may close out of numerical order.

2. The sweeper

   The lot closes. A sweeper finalises lots past their close, after a settlement grace window that honours a bid whose effective time was before the close but which was observed seconds later. The highest bid at or above any reserve wins; below reserve the lot is passed; with no bids it is unsold. A contract of sale forms between the winner and the consignor.

3. The engine

   The invoice issues. Hammer price plus the tiered marginal auction house fee: 7.5% on the first $2,500 stepping down to 3.9% above $1,000,000, applied per band like tax brackets. Denominated in dollars, payable within 10 days. Conditions of Sale §4.

Payment#

1. The settler

   If the winner was collateralised. The settler calls settle(bidder, lot, amount). The locked amount, up to the invoice total, moves from the contract to the immutable treasury address and the invoice is marked paid. A lock must have stood for SETTLE_DELAY, two minutes, before any of it can settle, and any part of the lock above the settled amount is released in the same transaction. settle.

2. The buyer

   Otherwise, the buyer pays the invoice. In USDC, from their own wallet, at one to one against the dollar figure. If they need to convert dollars first, they do that with Peer Pay, an independent third party, under its own terms. Minthouse holds no funds at any point in an onramp and earns nothing from one. Custody and settlement.

3. The indexer

   Booking. A payment is booked when it is 40 blocks deep, which is the same depth the indexer treats as final. Title to the lot transfers on confirmed payment, not before.

Delivery and settlement to the consignor#

1. The buyer

   The buyer chooses where the card goes. Take delivery, or keep it in the Minthouse vault. Ownership moved with the sale either way; this decides only whether a parcel leaves the building. Keeping it is constructive delivery, and both clocks below run from the date custody is recorded rather than from a delivery that never happens. Conditions of Sale §5.

2. The house

   Shipment. Arranged with the desk after settlement and quoted separately. The holder is inspected against tamper and counterfeit markers again before it leaves. International shipments clear at the buyer's expense.

3. The buyer

   The buyer protection window. Seven days from delivery, or from the date a kept card's custody is recorded, in which to raise an authenticity claim in writing or open a dispute. A dispute opened inside the window holds settlement while the desk decides. Authenticity and enforcement.

4. The house

   The consignor is paid. In USDC, once the buyer's payment has cleared, the card has been delivered or kept in the vault, and the seven-day window has run with no dispute open. An open dispute holds the proceeds until it resolves.

5. The engine

   The ledgers update themselves. The paid invoice becomes an acquisition row in the buyer's portfolio and the settled consignment becomes a disposal row in the consignor's, both by derivation rather than by a hook in the settlement path, and both exactly once. The custody ledger follows the same discipline on the same pass: ownership of the object moves to the buyer, and a sale the house later unwinds reverses the money and returns the object, on both ledgers, automatically. Portfolio engine, The vault.

What a losing bidder does#

Nothing, if they do not want to. A losing bidder's balance stays theirs in the escrow contract, and being outbid releases the lock against it. To take the money out:

1. The bidder

   Request. requestWithdraw(amount) against free balance. This starts a timelock, one hour on this deployment, and the house counts the pending amount against bidding power the moment it lands, which is the point: funds cannot back a standing bid and walk out before the lot closes.

2. The bidder

   Claim. After the delay, claimWithdraw(). This function is not pausable, requires no signature or cooperation from Minthouse, and cannot be blocked by the house under any state the contract can reach. Guarantee 2.