The Complete Auction Glossary: All Terms Every Bidder, Seller, and Auction House Should Know
Auctions have their own language, and it is not a small one. A single sale can involve a consignor, a reserve, an increment schedule, a soft close, a buyer's premium, and a settlement date — and each of those words carries real financial consequence for someone in the room.
This glossary collects 399 terms in one place, organised A–Z. Whether you are placing your first absentee bid, running a hybrid live-and-online sale, or writing terms and conditions for a platform, the definitions below are written to be short, plain, and usable.
A
88 terms
Absentee bidding — Leaving a maximum bid with the auction house in advance so the lot can be bid on your behalf while you are away.
Absolute auction — A sale with no reserve and no minimum: the lot goes to the highest bidder whatever that bid turns out to be.
Additional buyer's premium — A supplementary percentage charged on top of the standard premium, often applied to online or third-party platform bidding.
Advance bidding — Bids submitted during the window between catalogue publication and the opening of live bidding.
Agent bidding — Bidding executed by a software agent following rules the bidder has set in advance.
All-pay auction — A format in which every participant forfeits their bid whether or not they win; used in research and in some charity formats.
Appraisal value — A professional opinion of an item's worth, produced before consignment to guide estimates and reserves.
As-is condition — A disclaimer that the lot is sold in its present state, with no warranty as to condition or completeness.
Ascending bid auction — The familiar open format in which prices rise until only one bidder remains; also called an English auction.
Auction access — The permissions and credentials that determine which users may view, register for, or bid in a given sale.
Auction agents — People or software authorised to bid, buy, or manage lots on another party's behalf.
Auction agreement — The contract between auctioneer and consignor setting commission, reserve, marketing, and settlement terms.
Auction analytics — Reporting on bidding activity, sell-through, price realisation, and bidder behaviour across sales.
Auction appraisals — Valuations produced specifically to support cataloguing, estimating, and insurance for an upcoming sale.
Auction bid history — The recorded sequence of bids on a lot, including amounts, timestamps, and bidder identifiers.
Auction bidding strategy — A bidder's plan for when to enter, how far to go, and how to respond to competition.
Auction block — The physical or notional place where a lot is offered; "on the block" means currently being sold.
Auction broker — An intermediary who connects buyers or sellers with the right auction venue and manages the process for them.
Auction business — The commercial operation of an auction house, including consignment, cataloguing, marketing, sale, and settlement.
Auction catalog — The published list of lots offered in a sale, with descriptions, estimates, images, and conditions of sale.
Auction cataloging — The work of researching, describing, photographing, and sequencing lots for a catalogue.
Auction channels — The routes through which bids arrive: in-room, online, telephone, absentee, and mobile.
Auction clerk — The staff member who records winning bids, bidder numbers, and hammer prices during a live sale.
Auction commissions — The fees an auction house earns, charged to the seller, the buyer, or both.
Auction contract — The binding agreement governing a specific sale between the parties involved.
Auction contracts — The wider set of agreements — consignment, bidder, platform, settlement — that underpin an auction operation.
Auction customer service — Support provided to bidders and consignors before, during, and after a sale.
Auction day — The day a sale takes place, and the operational schedule that surrounds it.
Auction deadlines — Cut-off points for consignment, registration, bidding, payment, and collection.
Auction end date — The scheduled close of a timed or online sale.
Auction entry — The act of submitting a lot for inclusion in a sale, or of a bidder joining a sale.
Auction estimate — The price range the auction house expects a lot to achieve, published to guide bidders.
Auction floor — The room where live bidding takes place and the bidders present in it.
Auction hammer — The gavel used to signal that a lot has sold; by extension, the moment of sale.
Auction house — The business that organises and conducts sales on behalf of consignors.
Auction information packet — The bundle of documents given to registered bidders: terms, condition reports, legal descriptions, and payment details.
Auction information systems — The software that manages lots, bidders, bids, invoices, and settlement.
Auction instructions — Directions issued to bidders or staff covering registration, bidding procedure, and payment.
Auction listing — The published entry for an individual lot, with description, images, estimate, and bidding controls.
Auction lot — A single item or grouped set of items sold as one unit.
Auction marketplaces — Platforms that aggregate lots from multiple sellers or auction houses in one venue.
Auction markup — The difference between the hammer price and the total the buyer pays once fees are added.
Auction models — The structural variants of auction design — ascending, descending, sealed-bid, double, and so on.
Auction negotiations — Post-sale discussions on unsold lots, aftersale offers, or amended terms.
Auction online systems — The infrastructure that runs internet bidding, including timing, increments, and bid validation.
Auction platform features — The functional capabilities of an auction system: catalogue, registration, live bidding, payments, reporting.
Auction price history — The record of prices achieved for comparable lots over time.
Auction pricing model — How a sale sets estimates, reserves, increments, and fees.
Auction procedures — The documented steps that govern how a sale is run from opening to settlement.
Auction processing — The back-office work of invoicing, payment collection, release of goods, and consignor payout.
Auction qualification criteria — The requirements a bidder must meet to be approved, such as identity checks or deposits.
Auction registration systems — Tools for enrolling bidders, verifying identity, and issuing paddle numbers.
Auction regulations — The laws and rules governing auctioneering in a given jurisdiction.
Auction reserves — Confidential minimum prices below which lots will not be sold.
Auction resources — Guides, templates, and reference material supporting bidders and sellers.
Auction security features — Controls protecting bidder data, bid integrity, and payment information.
Auction selection criteria — The standards an auction house applies when deciding which property to accept.
Auction sellers — Consignors offering property for sale, from individuals to institutions.
Auction services — The full range of offerings around a sale: valuation, marketing, logistics, and settlement.
Auction software — Systems purpose-built to run auctions across live, online, and hybrid channels.
Auction strategies — Approaches used by sellers and buyers to maximise outcome, from lot sequencing to bid timing.
Auction terms — The rules and vocabulary that define how a sale operates.
Auction terms and conditions — The binding rules bidders accept at registration.
Auction terms of sale — The specific commercial terms applying to a sale: premium, payment window, collection, and default remedies.
Auction theory — The economic study of auction design, bidder incentives, and revenue outcomes.
Auction tips — Practical guidance for bidding effectively and avoiding common mistakes.
Auction tools — Utilities that support participation, such as watchlists, proxy bidding, and alerts.
Auction tracking — Monitoring lots, bids, and sale progress in real time.
Auction transaction costs — The total non-hammer costs of a sale: premiums, fees, taxes, shipping, and handling.
Auction trends — Movements in demand, pricing, and format adoption across a market.
Auction turnover rate — The proportion of offered lots that sell, and how quickly inventory moves.
Auction types — The main categories of sale: absolute, reserve, sealed-bid, Dutch, silent, charity, and more.
Auction types of listings — The listing formats available, such as single lot, multi-lot, timed, or buy-now.
Auction update — A notification of changes to a lot, schedule, or sale conditions.
Auction validation — Checks confirming that bids, bidders, and results are legitimate before finalisation.
Auction website design — The structure and interface of an auction site, shaping how bidders find and bid on lots.
Auction website features — Site capabilities such as search, filtering, live streaming, and saved searches.
Auctioneer — The licensed professional who conducts the sale and calls the bids.
Auctioneer bidding — Bids taken by the auctioneer on the seller's behalf up to the reserve, where permitted and disclosed.
Auctioneer compensation — How an auctioneer is paid: commission, flat fee, or a combination.
Auctioneer's fee — The charge for conducting a specific sale.
Auctioneer's fees — The full schedule of charges an auctioneer levies across services.
Auctioneer's role — Running the sale fairly: opening lots, managing increments, recognising bids, and closing at the hammer.
Auctioneering — The profession and practice of conducting auctions.
Auctioneering association — A professional body setting standards, ethics, and training for auctioneers.
Auctions with reserve — Sales in which lots carry a confidential minimum and may be withdrawn if it is not met.
Auto bid — A standing instruction that raises your bid automatically up to a maximum you set.
Auto-extend feature — A rule that pushes back the closing time when a late bid arrives, preventing last-second sniping.
B
56 terms
Back-up bidder — The underbidder who is next in line should the winning buyer default.
Ballroom auction — A live sale held in a large formal venue, typically for real estate or high-value property.
Bankruptcy auction — A court-supervised sale of a bankrupt estate's assets to repay creditors.
Bargain price — A winning bid materially below the item's market value.
Bid acceptance — The system's formal recognition that a bid is valid and recorded.
Bid adjustment — A change to a submitted or maximum bid, made manually or by an automated agent.
Bid cancellation — The removal of a bid, usually by the auctioneer, for error or rule breach.
Bid closing time — The moment after which no further bids are accepted.
Bid confirmation — The acknowledgement sent to a bidder that their bid was received and recorded.
Bid increment — The minimum amount by which each new bid must exceed the current high bid.
Bid retraction — A bidder's withdrawal of their own bid before the auction closes, where the rules allow it.
Bid rigging — Illegal collusion among bidders to suppress competition and fix outcomes.
Bid sniping — Placing a decisive bid in the final seconds to leave rivals no time to respond.
Bidder — Any person, organisation, or authorised agent placing bids in a sale.
Bidder agreement — The contract a bidder accepts setting out conduct, payment, and default terms.
Bidder alerts — Automated notifications about outbids, closing times, and lot changes.
Bidder approval — Vetting a registrant before allowing them to bid.
Bidder behavior analysis — Study of how bidders act — timing, aggression, drop-off — to inform sale design.
Bidder control — Rules and tools that regulate bidder conduct, such as limits, suspensions, and caps.
Bidder number — The unique identifier assigned to each registered bidder for tracking bids and invoices.
Bidder registration — The enrolment process granting a person the right to bid.
Bidder registration process — The full sequence of identity capture, verification, deposit, and approval.
Bidder statistics — Aggregated data on bidder participation, win rates, and spend.
Bidder tracking system — Software that records and analyses bidder activity through a sale.
Bidder's market — Conditions where supply exceeds demand, giving buyers the advantage.
Bidding agent — Software that places bids for a user according to preset rules.
Bidding contest — Active competition between bidders trading successive bids on a lot.
Bidding criteria — The rules by which bids are evaluated and a winner determined.
Bidding history — The full record of bids placed on a lot.
Bidding interface — The screen or panel through which bids are entered.
Bidding online — Participating in a sale electronically rather than in the room.
Bidding pattern analysis — Examining the shape of bidding over time to detect strategy or irregularity.
Bidding platform — The system that receives, validates, and processes bids.
Bidding platform rules — Platform-level rules ensuring fairness, transparency, and consistent handling of bids.
Bidding platform structure — The architecture that lets bidders compete reliably at scale.
Bidding process flow — The ordered steps from bid submission through validation to acceptance or rejection.
Bidding protection strategies — Safeguards against unfair practice, such as shill detection and bid throttling.
Bidding strategy — A bidder's systematic approach to how much to bid, when, and how to react.
Bidding trends — Patterns in bidding activity across lots, categories, or time.
Bidding war — Sustained aggressive competition between two or more bidders driving a price well above estimate.
Block bidding — Bidding on several lots together as a single package rather than individually.
Bonus time bidding — A dynamic close that extends the deadline each time a bid lands inside a set window.
Book value — The value of an asset as recorded in accounting records, distinct from market value.
Broker bidding — A licensed broker bidding on a client's behalf.
Broker participation — The involvement of intermediaries who bring buyers or sellers to a sale, often for a share of commission.
Brokerage fees — Charges levied by brokers or auction houses for facilitating a transaction.
Buy-sell agreement — A contract governing how ownership interests in a business or asset may be bought and sold.
Buyer participation — The level of active involvement by potential buyers in a sale.
Buyer premium — A percentage added to the hammer price and paid by the winning bidder.
Buyer's agent — A professional representing the buyer's interests through the auction process.
Buyer's commission — The auction house's charge to the buyer, calculated on the hammer price.
Buyer's fee structure — The complete schedule of costs a buyer pays beyond the winning bid.
Buyer's market auction — A sale where supply outstrips demand and purchasers hold the leverage.
Buyer's payment options — The methods a buyer may use to settle: card, wire, cashier's check, financing, or escrow.
Buyer's remorse — Regret after winning, typically from overbidding or an impulsive decision.
Buyout price — A fixed amount that lets a bidder purchase immediately and end the bidding.
C
28 terms
Candle auction — A historical format in which bidding ran until a burning candle went out.
Cashier check — A bank-guaranteed payment instrument drawn on the bank's own funds.
Catalog auction — A sale in which every lot is listed in advance with descriptions and images.
Catalog description — The written account of a lot's identity, condition, provenance, and measurements.
Catalog image — The photograph representing a lot in the catalogue and listing.
Certificate of sale — Documentation confirming a completed auction purchase, often used in legal or foreclosure sales.
Closing bid analysis — Review of final bids to understand pricing outcomes and demand.
Closing date — The date a sale ends or a transaction completes.
Closing statement — An itemised statement of the amounts due and paid at completion.
Commission agreement — The contract fixing what the auction house earns on a sale.
Common value auction — A format where the item's true value is the same for everyone but unknown at bid time.
Competitive auction — A sale with enough active bidders to drive genuine price discovery.
Competitive bidding — Open rivalry between bidders to secure a lot.
Competitive bidding behavior — How bidders act under competition — escalation, jump bids, or withdrawal.
Condition report — A detailed account of a lot's physical state, including damage and restoration.
Consignment — Placing property with an auction house to be sold on the owner's behalf.
Consignor — The owner who submits property for sale.
Consignor evaluation — Assessment of a consignor's property and terms before acceptance.
Consumer auction — A sale aimed at retail buyers rather than trade or institutional bidders.
Consumer auction websites — Online platforms serving general-public bidders.
Contract of sale — The binding agreement transferring ownership from seller to buyer.
Credit bid — A bid by a secured creditor using debt owed to them instead of cash.
Current auction bid — The highest bid standing at this moment in a live or timed sale.
Current bid — The prevailing high bid on a lot.
Current inventory — The lots presently available for sale.
Current market auction — A sale priced and conducted against present market conditions.
Current value auction — A format where pricing reflects up-to-date valuation rather than historical cost.
Customary closing costs — The standard fees and charges routinely paid at completion.
D
16 terms
Dealer auction — A trade-only sale restricted to licensed or professional buyers.
Decline in price — A downward movement in realised prices across a category or sale.
Deferred payment — An arrangement permitting the buyer to pay after the usual settlement window.
Deposit requirement — Funds a bidder must lodge before being approved to bid.
Descending bid auction — A format starting high and falling until someone accepts; a Dutch auction.
Detailed auction terms — The full, itemised conditions governing a sale.
Digital auction systems — End-to-end software running catalogue, bidding, payment, and reporting online.
Digital auction tools — Individual features supporting online participation, from watchlists to live video.
Disclosure statement — A seller's declaration of known defects or material facts about a lot.
Dispute resolution — Mechanisms for settling disagreements between bidders, sellers, and the auction house.
Dispute resolution process — The defined steps — notice, review, mediation, decision — for handling a claim.
Double auction — A market where buyers and sellers submit bids and offers simultaneously and are matched.
Duration of auction — How long a sale remains open for bidding.
Dutch auction — A descending-price format where the first bidder to accept wins.
Dynamic closing — Automatic extension of the close whenever late bids arrive.
Dynamic pricing auction — A format where price adjusts continuously in response to demand.
E
10 terms
Earnest money — A good-faith deposit securing a buyer's commitment to complete.
End time — The scheduled close of bidding on a lot or sale.
Entry fee — A charge to enter a lot into a sale or to register as a bidder.
Estate auction — A sale of the contents or assets of an estate, often following a death or downsizing.
Estimated value — The expected price range for a lot, published ahead of the sale.
Event fee — A charge covering the cost of staging a particular sale event.
Exclusive auction bidding — Bidding restricted to a defined, invited, or pre-qualified group.
Exclusive right to sell — A contract giving one auction house sole authority to sell the property.
External auction platform — A third-party site carrying an auction house's lots to a wider audience.
External bidding — Bids arriving through a third-party platform rather than the house's own system.
F
13 terms
Fair market value — The price a willing buyer and willing seller would agree with neither under compulsion.
Fall of the hammer — The moment the auctioneer closes a lot and the contract of sale forms.
Final bid — The last and highest bid accepted on a lot.
Fixed price auction — A listing sold at a set price rather than through competitive bidding.
Fixed value auction — A format where lot values are predetermined rather than discovered by bidding.
Floor auctions — Sales conducted in the room with bidders physically present.
Floor bid — A bid placed by a bidder present in the saleroom.
Floor price — The minimum acceptable price for a lot.
Forward auction — The standard format: one seller, many buyers competing upward.
Fraudulent bidding — Deceptive bidding such as shill bids or bids placed with no intent to pay.
Full reserve auction — A sale in which every lot carries a reserve.
Fundamental auction strategy — Core principles of bidding: set a limit, understand increments, know the fees.
Future bidding trends — Anticipated shifts in how and where bidders participate.
G
4 terms
Gavel — The auctioneer's mallet, struck to mark a completed sale.
General auction procedure — The standard order of operations for conducting a sale.
Government auction — A public sale of surplus, seized, or forfeited government property.
Guide price — An indicative figure published to help bidders gauge likely value.
H
7 terms
Hammer price — The winning bid at the fall of the hammer, before premium and taxes.
Hidden reserve — A reserve kept confidential from bidders during the sale.
High bid — The current leading bid on a lot.
High bidder — The bidder currently holding the leading position.
High-value items — Lots of substantial worth, usually subject to extra vetting, security, and payment terms.
House bid — A bid entered by the auction house, typically to advance toward a reserve where disclosed and permitted.
Hybrid auction — A sale combining live in-room bidding with simultaneous online and phone participation.
I
10 terms
Increment bidding — Bidding in the fixed steps set by the increment schedule.
Individual auction strategies — Bidding approaches tailored to a single bidder's budget and goals.
Individual lot auction — Selling lots one at a time rather than as a package.
Initial reserve bid — The first bid level at which the reserve is considered met.
Initial sale price — The price at which bidding on a lot begins.
Inspection period — The window in which bidders may examine lots before bidding.
Instant purchase — Buying immediately at a fixed price without bidding.
Interactive auction platforms — Systems offering live video, chat, and real-time bid feedback.
Internet bidding — Placing bids over the web during live or timed sales.
Item description — The written detail of a lot's attributes and condition.
J
3 terms
Judicial auction — A court-ordered sale of property, typically to satisfy a judgment or debt.
Jump bid — A bid substantially above the next increment, used to intimidate rivals.
Jumping the bid — Bidding out of turn or above the called increment, disrupting the auctioneer's rhythm.
K
2 terms
Knockdown — The sale of a lot at the fall of the hammer; the knockdown price is the hammer price.
Knockout agreement — An illegal pact among bidders to suppress bidding and split the gain afterwards.
L
8 terms
Late bid — A bid arriving at or after the scheduled close, which may trigger an extension or be rejected.
Legal description — The formal legal identification of a property, used in real estate sales.
Listing broker — The broker representing the seller and marketing the property.
Live auction — A real-time sale conducted by an auctioneer calling bids.
Live auction events — Scheduled in-person sales, often with preview and reception elements.
Live bidding system — Technology synchronising in-room, phone, and online bids in real time.
Lot number — The identifier marking a lot's place in the sale order.
Lotting sequence — The deliberate order in which lots are offered to maximise attention and price.
M
14 terms
Market estimates — Value ranges derived from comparable sales data.
Market value — What an item would realistically fetch in an open, competitive market.
Market value range — The spread between plausible low and high outcomes for a lot.
Market-driven auction — A sale whose pricing and format respond directly to current demand.
Max bid set for auction — The ceiling a bidder authorises their proxy or agent to reach.
Maximum bid — The highest amount a bidder is willing to pay.
Minimum bid — The lowest bid the auctioneer will accept to open a lot.
Minimum price — The floor below which a lot will not be sold.
Minimum reserve price — The lowest confidential reserve a seller will accept.
Mock auction — A staged or deceptive sale designed to mislead buyers; illegal in many jurisdictions.
Multi-channel auctions — Sales that accept bids simultaneously across in-room, online, phone, and mobile.
Multi-lot auction — A sale offering many lots in sequence.
Multi-party auction — A sale involving multiple sellers, owners, or stakeholders in the proceeds.
Multi-property auction — A real estate sale offering several properties in one event.
N
5 terms
National Auctioneers Association — A professional body providing standards, education, and certification for auctioneers.
No reserve auction — A sale where lots will sell at whatever the highest bid turns out to be.
No sale — A lot that fails to meet its reserve and goes unsold.
Notarized deed — A deed formally witnessed and certified by a notary for legal transfer.
Notice of sale — Formal public notification that an auction will take place, often legally required.
O
11 terms
Off-the-floor bidding — Bids from outside the saleroom, via phone, internet, or absentee order.
Offer and acceptance — The legal mechanism by which a bid and its acceptance form a binding contract.
On-site auction — A sale conducted at the location of the property being sold.
Online auction — A sale conducted entirely over the internet.
Online auction analysis — Reporting on traffic, registrations, bidding depth, and outcomes for a digital sale.
Online auction site fees — The charges a platform levies on listings, transactions, or payments.
Open bid auction — A format where all bids are visible to participants as they are placed.
Opening bid — The first bid accepted on a lot.
Outbid notice — An alert telling a bidder they no longer hold the leading position.
Overbidding regulations — Rules limiting or governing bids that exceed reasonable or permitted levels.
Owner's confirmation — The seller's approval required before an under-reserve sale can be finalised.
P
22 terms
Paddle number — The number on a registered bidder's paddle, used to identify them to the auctioneer.
Parcel auction — A property sale where land is offered in parcels, combinations, or as a whole.
Partial interest auction — The sale of a fractional ownership stake rather than the entire asset.
Participation deposit — Funds lodged to secure the right to bid, refunded to unsuccessful bidders.
Participation requirements — The conditions a bidder must satisfy to take part.
Payment terms — When and how the buyer must settle, and the consequences of failing to.
Penny auction — A pay-per-bid format where each bid costs a fee and nudges the price up by a small amount.
Perceived value auction — A sale where outcomes are driven by buyer perception rather than appraised worth.
Phone bidding — Bidding live by telephone through a member of auction house staff.
Pre-auction estimate — The published value range issued before the sale opens.
Pre-bid — A bid submitted before live bidding begins.
Pre-bid registration — Enrolling and being approved in advance of the sale.
Preview period — The window when lots can be inspected in person before bidding.
Price fluctuation auction — A format where prices move up or down in response to live demand.
Price realization — The actual price achieved, used to measure performance against estimate.
Pricing structure — How estimates, reserves, increments, and fees are set for a sale.
Private auction — A sale where bidder identities are concealed from other participants.
Private listings — Lots offered discreetly rather than through public catalogue.
Proxy bid — An instruction to bid automatically on your behalf up to a stated maximum.
Public auction — A sale open to any registered member of the public.
Public bidding process — Bidding conducted openly, with visible bids and transparent rules.
Purchase agreement — The contract setting out the terms of the completed sale.
Q
4 terms
Qualification terms — The criteria determining whether a bidder is approved to participate.
Qualified bidder — A bidder who has met identity, financial, and registration requirements.
Qualified buyers — Buyers verified as able to complete the purchase.
Quick sale auction — A compressed-timeline sale designed to convert assets to cash rapidly.
R
20 terms
Re-auction process — Re-offering a lot after a failed sale or a buyer default.
Real estate auction — A sale of land or property conducted by competitive bidding.
Real-time auction analytics — Live dashboards tracking bids, bidders, and price movement during a sale.
Real-time online auction — An internet sale where bids and results update instantly for all participants.
Reduced buyer's premium — A lower premium rate applied to certain categories, channels, or price bands.
Refundable deposit — A bidding deposit returned when a bidder does not win or completes payment.
Registration deposit — Funds required at registration to qualify a bidder.
Relisted lot — A previously unsold lot offered again in a later sale.
Remote bidding — Participating from outside the venue via online, phone, or absentee channels.
Reserve amount — The specific confidential minimum figure attached to a lot.
Reserve auction — A sale where lots will not sell below their reserve.
Reserve price — The lowest price a seller will accept, usually undisclosed.
Reserve price rules — The conditions governing how reserves are set, disclosed, and applied.
Reserves not met — The status of a lot whose highest bid fell short of its reserve.
Return policy — The terms, if any, under which a buyer may return a purchase.
Revenue from auctions — Total income generated by a sale across hammer, premiums, and fees.
Reverse auction — A format where sellers compete to offer the lowest price to a single buyer.
Reverse bidding auction — A procurement-style sale where prices fall as suppliers undercut each other.
Rollback auction — A format in which the price steps back to a lower level under defined conditions.
Room auction — A live sale conducted with bidders assembled in a saleroom.
S
40 terms
Sale pending — A lot under contract but not yet completed.
Sales contract — The binding agreement documenting the sale terms.
Sales proceeds — The net amount paid to the consignor after commission and expenses.
Sealed bid auction — A format where bids are submitted confidentially and opened together.
Sealed bid format — The procedural rules governing confidential bid submission and opening.
Second price auction — A sealed-bid format where the highest bidder wins but pays the second-highest bid.
Self-service auction site — A platform where sellers list and manage their own lots.
Seller disclosure rules — Requirements obliging sellers to reveal known material defects.
Seller protection — Safeguards shielding sellers from non-payment and fraudulent bidding.
Seller's bid history — The record of a seller's past sales and results.
Seller's disclosure — The seller's written statement of known issues affecting a lot.
Seller's listing — The published offer of a lot by its seller.
Seller's market — Conditions where demand exceeds supply and sellers hold the advantage.
Seller's market strategies — Tactics such as low estimates and tight reserves that exploit strong demand.
Selling broker — The broker who introduces the eventual buyer and shares in commission.
Selling strategy — The plan covering timing, format, reserve, estimate, and marketing for a consignment.
Service auction platform — A marketplace where services rather than goods are bid on.
Service-based auctions — Sales in which labour, contracts, or services are the lots.
Settlement date — The date payment and transfer must be completed.
Silent auction — A format where bids are written on sheets and the highest at close wins, with no auctioneer.
Silent auction events — Fundraising occasions built around silent bidding, often alongside a live sale.
Silent online auctions — Digital silent auctions where bids are placed through an app or site.
Simulcast auction — A live sale broadcast in real time so remote bidders compete alongside the room.
Single item auctions — Sales dedicated to one lot, typically of exceptional value.
Site security — Protections covering platform data, accounts, and payment integrity.
Smart contract auctions — On-chain sales where bidding, escrow, and settlement execute automatically in code.
Snipe auction strategies — Tactics built around bidding at the last possible moment.
Sniping — Placing a winning bid in the closing seconds to deny rivals a response.
Soft close — A closing rule that extends the deadline after late bids, so lots end only when bidding stops.
Spike bid behavior — Sudden sharp jumps in bid value, often signalling determined or automated bidders.
Standard auction platforms — Conventional systems supporting catalogue, registration, bidding, and settlement.
Standard auction procedures — The accepted operational norms for running a compliant sale.
Standard online auction practices — Common conventions in digital sales: proxy bidding, soft close, published increments.
Standardized bidding process — A uniform, documented bidding procedure applied consistently across lots.
Starting bid — The amount at which bidding opens on a lot.
Starting price strategy — Setting the opening figure to attract entry while protecting value.
Statutory auction — A sale mandated and governed by statute, such as tax or lien sales.
Step bidding — Bidding in defined increments rather than arbitrary amounts.
Strategic auction planning — Designing the sale — timing, lotting, marketing, reserves — to maximise results.
Subject to confirmation — A sale conditional on the seller's later approval of the highest bid.
T
13 terms
Tax deed auction — A public sale of property to recover unpaid property taxes.
Tax-deferred auctions — Sales structured so tax liability is postponed, as in a like-kind exchange.
Term of sale — An individual condition within the sale terms.
Terms and conditions — The complete binding rules governing participation and purchase.
Tie bid — Two identical bids, resolved by timestamp, rule, or a tie-break round.
Time extension — Additional bidding time granted when late bids arrive.
Time-sensitive auctions — Sales run against a tight deadline, such as liquidation or perishable goods.
Title search — Investigation of ownership records to confirm clear title before transfer.
Title transfer — The legal passing of ownership from seller to buyer.
Traditional auction — A conventional in-person sale conducted by an auctioneer.
Traditional vs digital auctions — The comparison of in-room sales with online formats on reach, cost, and pace.
Transparent auction policies — Published rules on fees, reserves, and bidding that let participants see how the sale works.
Trustee sale — A foreclosure sale conducted by a trustee under a deed of trust.
U
7 terms
Underbid situation — Where the highest bid falls short of the reserve or expected value.
Underpricing auctions — Setting estimates or opening bids deliberately low to stimulate competition.
Unreserved auction — A sale where every lot sells regardless of price.
Upset price — A statutory or court-set minimum below which a lot cannot be sold.
User feedback on auctions — Ratings and reviews from participants about their experience.
User tracking — Monitoring on-platform behaviour to improve service and detect irregularity.
User-controlled bidding — Bidding managed directly by the bidder rather than delegated to an agent.
V
6 terms
Value estimate — An assessed range of what a lot is expected to realise.
Vendor bid — A bid made by or for the seller, where permitted and disclosed.
Vendor participation — The seller's involvement in the sale process and its conditions.
Vickrey auction — A sealed-bid, second-price format designed to encourage truthful bidding.
Virtual auction — A sale held entirely online with no physical saleroom.
Virtual lot closing — Staggered digital closing of lots, typically a few seconds or minutes apart.
W
10 terms
Watchlist tracking — Saving lots to monitor and receive alerts on their status.
Website-based auction — A sale conducted through a dedicated auction website.
Winner-take-all auction — A format where a single winner takes the entire prize or asset.
Winning auction price — The final price the successful bidder pays.
Winning bid — The highest accepted bid at the close.
Winning bidder — The participant who secures the lot.
With reserve — Indicating a lot carries a confidential minimum price.
Withdrawn lot — A lot removed from the sale before or during bidding.
Without reserve — Indicating a lot will sell to the highest bidder whatever the amount.
Workout plan auction — A sale forming part of a negotiated restructuring of distressed debt or assets.
Y
1 term
Yard auction — An informal outdoor sale of household goods and miscellaneous items.
Z
1 term
Zero-sum bidding — Competition in which one bidder's gain is exactly another's loss, with no shared upside.
Putting the vocabulary to work
A handful of these terms do most of the work in practice. If you learn five, learn these:
- Hammer price is not what you pay. Buyer's premium, taxes, and shipping sit on top of it.
- Reserve decides whether a lot sells at all. A strong bid under reserve is still a no sale.
- Increment determines the shape of the contest — small steps invite long bidding wars, large ones end them fast.
- Soft close and auto-extend exist to neutralise sniping. Know which your platform uses before the final minute.
- Proxy bid protects you from yourself. Set a maximum before the emotion starts.
The rest of the glossary fills in around those five. Bookmark this page and come back to it when a term in a condition report or a set of terms and conditions stops you.