Running the Platform Glossary · Investing

Account shard: one slice of a broker's or exchange's accounts with its own application servers, database and deploy pipeline, so a failure or a release touches only that slice (Trading Platform Architecture).
Account shard mapping: the stored record of which shard holds an account, read by the router and cached, so an account can move without rehashing every other (Trading Platform Architecture).
Active brokerage account: Schwab's count of brokerage accounts with activity in the preceding 270 days (Investing & Digital Assets Metrics).
Agent mandate: the customer's stored authorization for a software agent trading an account: instruments, order types, per-order and daily limits, hours and expiry, checked by the platform on every order (AI in Investing).
AI washing: claiming in marketing or filings to use AI that a firm doesn't use as described; the SEC's 2024 actions against Delphia and Global Predictions (AI in Investing).
ARPU (broker): total revenue over the average of funded customers at the end of the period and the prior period, annualized in quarterly releases (Investing & Digital Assets Metrics).
Brokerage conversion: moving accounts in bulk from one platform or firm to another without each customer's transfer instruction, in batches with a freeze, load, reconciliation and go decision (Conversions, Shutdowns & Distributions).
Business continuity plan (FINRA 4370): a broker-dealer's written plan for meeting obligations to customers through a significant business disruption, covering at least ten listed areas including mission critical systems and alternate customer communications (Peak Days, Outages & Resilience).
Control total: a sum or count taken from the source and the target of a migration at one level (accounts, positions, shares, cash, lots, adjusted basis) and compared before going live (Conversions, Shutdowns & Distributions).
Core net new assets: Schwab's net new client assets before significant one-time flows such as acquisitions (Investing & Digital Assets Metrics).
Covered technology: in the SEC's withdrawn 2023 proposal, any analytical function that optimizes for, predicts, guides, forecasts or directs investment-related behaviors or outcomes in an investor interaction (AI in Investing).
DARTs: daily average revenue trades, customer orders that generate revenue per trading day, as Interactive Brokers reports them (Investing & Digital Assets Metrics).
Degraded mode: a deliberate, scoped state (cancel-only, close-only, read-only, withdrawals paused, a feature off) that the platform enters during an incident, with a runbook and a customer message (Peak Days, Outages & Resilience).
Device binding: a record that a customer proved a device with a passkey or device key, used as evidence that later instructions from it come from the customer (Account Security & Fraud).
Distribution agent: a firm a bankruptcy estate uses to pay creditors in cash or crypto, such as PayPal and Coinbase in the Celsius case (Conversions, Shutdowns & Distributions).
Entity partition: the region, database cluster and shards that hold one legal entity's data, recorded as a row so the entity can be moved, isolated or wound down (Trading Platform Architecture).
Escheatment: turning unclaimed money over to the state after a dormancy period (Conversions, Shutdowns & Distributions).
Funded customer: Robinhood's count of unique people with an account at any of its entities that had a positive balance (excluding firm-granted promotions) or a transaction in the past 45 days (Investing & Digital Assets Metrics).
Indication of interest (unclaimed property): an owner's act that restarts the dormancy clock, such as a communication about the property or owner-directed activity in the account, as Delaware's law lists them (Conversions, Shutdowns & Distributions).
Invariant check: a stored query that must return no rows (an entry that doesn't balance, a ledger-to-chain difference, a negative balance without credit), run on a schedule with its result kept (Trading Platform Architecture).
Market exit: a platform stopping service to a country or state, run as a sequence of states from notice to close-only, withdraw-only and final disposition (Conversions, Shutdowns & Distributions).
Meaningful wallet: Circle's count of on-chain wallets holding at least $10 of USDC (Investing & Digital Assets Metrics).
Mission critical system: under FINRA 4370, any system needed for prompt and accurate processing of securities transactions, from order taking and execution to access to customer accounts and delivery of funds and securities (Peak Days, Outages & Resilience).
Monthly transacting user (MTU): Coinbase's count of consumers who actively or passively transacted at least once in a rolling 28 days (Investing & Digital Assets Metrics).
Negative response letter: a notice telling customers their accounts will move in a bulk transfer unless they object within at least 30 days, accepted by FINRA in listed circumstances (Conversions, Shutdowns & Distributions).
Net deposits: money and assets customers brought in, plus dividends, interest, staking rewards and promotions, less withdrawals, transfers out, interest and subscription fees charged; distinct from performance external flows (Investing & Digital Assets Metrics).
Outage compensation: a payment to a customer for a trade an outage prevented, computed from a logged attempt, the price at the attempt and the first reasonable opportunity after recovery (Peak Days, Outages & Resilience).
Posting service: the one writer of journal entries, holds and positions; every other service asks it to move money or assets (Trading Platform Architecture).
Restitution payment: money or assets a firm pays a customer for a loss outside a platform security incident, by firm error, voluntary policy, a regulator's order, an award or a settlement (Account Security & Fraud).
SCI entity: a self-regulatory organization, an ATS over Regulation SCI's volume thresholds, a plan processor, certain exempt clearing agencies or a competing consolidator, subject to the SEC's systems resilience rule; not a broker-dealer as such (Peak Days, Outages & Resilience).
SCI event: a systems disruption, systems compliance issue or systems intrusion at an SCI entity, with corrective action and notice to the SEC immediately and in writing within 24 hours (Peak Days, Outages & Resilience).
Security change hold: a withdrawal hold placed when value is sent to a destination added after a password, contact, 2FA or device change, with notice to the contact points that existed before the change (Account Security & Fraud).
Sequenced input: an order, fill, deposit or other instruction given a gapless per-account sequence number before it's applied, so the account's state can be replayed in order (Trading Platform Architecture).
SIM swap: moving a customer's phone number to an attacker's SIM or carrier to receive their SMS codes; carriers must authenticate and notify under the FCC's 2023 order (Account Security & Fraud).
Surge factor: the multiple of a normal peak a capacity plan is built for, set from the platform's history and public peaks such as Robinhood's 7x in 2020 (Peak Days, Outages & Resilience).
Take rate: net revenue over gross volume, in basis points, read with its mix (Investing & Digital Assets Metrics).
Withdrawal hold: a stop on one outbound transfer for a stated reason (a new destination, a security change, risk review, a customer lock, a senior investor hold, a legal order), released by a timer, the customer or a reviewer (Account Security & Fraud).

Account shard: one slice of a broker's or exchange's accounts with its own application servers, database and deploy pipeline, so a failure or a release touches only that slice (Trading Platform Architecture).
Account shard mapping: the stored record of which shard holds an account, read by the router and cached, so an account can move without rehashing every other (Trading Platform Architecture).
Active brokerage account: Schwab's count of brokerage accounts with activity in the preceding 270 days (Investing & Digital Assets Metrics).
Agent mandate: the customer's stored authorization for a software agent trading an account: instruments, order types, per-order and daily limits, hours and expiry, checked by the platform on every order (AI in Investing).
AI washing: claiming in marketing or filings to use AI that a firm doesn't use as described; the SEC's 2024 actions against Delphia and Global Predictions (AI in Investing).
ARPU (broker): total revenue over the average of funded customers at the end of the period and the prior period, annualized in quarterly releases (Investing & Digital Assets Metrics).
Brokerage conversion: moving accounts in bulk from one platform or firm to another without each customer's transfer instruction, in batches with a freeze, load, reconciliation and go decision (Conversions, Shutdowns & Distributions).
Business continuity plan (FINRA 4370): a broker-dealer's written plan for meeting obligations to customers through a significant business disruption, covering at least ten listed areas including mission critical systems and alternate customer communications (Peak Days, Outages & Resilience).
Control total: a sum or count taken from the source and the target of a migration at one level (accounts, positions, shares, cash, lots, adjusted basis) and compared before going live (Conversions, Shutdowns & Distributions).
Core net new assets: Schwab's net new client assets before significant one-time flows such as acquisitions (Investing & Digital Assets Metrics).
Covered technology: in the SEC's withdrawn 2023 proposal, any analytical function that optimizes for, predicts, guides, forecasts or directs investment-related behaviors or outcomes in an investor interaction (AI in Investing).
DARTs: daily average revenue trades, customer orders that generate revenue per trading day, as Interactive Brokers reports them (Investing & Digital Assets Metrics).
Degraded mode: a deliberate, scoped state (cancel-only, close-only, read-only, withdrawals paused, a feature off) that the platform enters during an incident, with a runbook and a customer message (Peak Days, Outages & Resilience).
Device binding: a record that a customer proved a device with a passkey or device key, used as evidence that later instructions from it come from the customer (Account Security & Fraud).
Distribution agent: a firm a bankruptcy estate uses to pay creditors in cash or crypto, such as PayPal and Coinbase in the Celsius case (Conversions, Shutdowns & Distributions).
Entity partition: the region, database cluster and shards that hold one legal entity's data, recorded as a row so the entity can be moved, isolated or wound down (Trading Platform Architecture).
Escheatment: turning unclaimed money over to the state after a dormancy period (Conversions, Shutdowns & Distributions).
Funded customer: Robinhood's count of unique people with an account at any of its entities that had a positive balance (excluding firm-granted promotions) or a transaction in the past 45 days (Investing & Digital Assets Metrics).
Indication of interest (unclaimed property): an owner's act that restarts the dormancy clock, such as a communication about the property or owner-directed activity in the account, as Delaware's law lists them (Conversions, Shutdowns & Distributions).
Invariant check: a stored query that must return no rows (an entry that doesn't balance, a ledger-to-chain difference, a negative balance without credit), run on a schedule with its result kept (Trading Platform Architecture).
Market exit: a platform stopping service to a country or state, run as a sequence of states from notice to close-only, withdraw-only and final disposition (Conversions, Shutdowns & Distributions).
Meaningful wallet: Circle's count of on-chain wallets holding at least $10 of USDC (Investing & Digital Assets Metrics).
Mission critical system: under FINRA 4370, any system needed for prompt and accurate processing of securities transactions, from order taking and execution to access to customer accounts and delivery of funds and securities (Peak Days, Outages & Resilience).
Monthly transacting user (MTU): Coinbase's count of consumers who actively or passively transacted at least once in a rolling 28 days (Investing & Digital Assets Metrics).
Negative response letter: a notice telling customers their accounts will move in a bulk transfer unless they object within at least 30 days, accepted by FINRA in listed circumstances (Conversions, Shutdowns & Distributions).
Net deposits: money and assets customers brought in, plus dividends, interest, staking rewards and promotions, less withdrawals, transfers out, interest and subscription fees charged; distinct from performance external flows (Investing & Digital Assets Metrics).
Outage compensation: a payment to a customer for a trade an outage prevented, computed from a logged attempt, the price at the attempt and the first reasonable opportunity after recovery (Peak Days, Outages & Resilience).
Posting service: the one writer of journal entries, holds and positions; every other service asks it to move money or assets (Trading Platform Architecture).
Restitution payment: money or assets a firm pays a customer for a loss outside a platform security incident, by firm error, voluntary policy, a regulator's order, an award or a settlement (Account Security & Fraud).
SCI entity: a self-regulatory organization, an ATS over Regulation SCI's volume thresholds, a plan processor, certain exempt clearing agencies or a competing consolidator, subject to the SEC's systems resilience rule; not a broker-dealer as such (Peak Days, Outages & Resilience).
SCI event: a systems disruption, systems compliance issue or systems intrusion at an SCI entity, with corrective action and notice to the SEC immediately and in writing within 24 hours (Peak Days, Outages & Resilience).
Security change hold: a withdrawal hold placed when value is sent to a destination added after a password, contact, 2FA or device change, with notice to the contact points that existed before the change (Account Security & Fraud).
Sequenced input: an order, fill, deposit or other instruction given a gapless per-account sequence number before it's applied, so the account's state can be replayed in order (Trading Platform Architecture).
SIM swap: moving a customer's phone number to an attacker's SIM or carrier to receive their SMS codes; carriers must authenticate and notify under the FCC's 2023 order (Account Security & Fraud).
Surge factor: the multiple of a normal peak a capacity plan is built for, set from the platform's history and public peaks such as Robinhood's 7x in 2020 (Peak Days, Outages & Resilience).
Take rate: net revenue over gross volume, in basis points, read with its mix (Investing & Digital Assets Metrics).
Withdrawal hold: a stop on one outbound transfer for a stated reason (a new destination, a security change, risk review, a customer lock, a senior investor hold, a legal order), released by a timer, the customer or a reviewer (Account Security & Fraud).