Vault

Reading depth

Each view includes the earlier layers; the complete engineer or auditor page is shown by default.

BeginnerCore purpose and mental modelPractitionerAdds mechanisms and economicsEngineer or auditorAdds state and verification

Dependency check

Advanced detail assumes prerequisite knowledge

Before using practitioner mechanisms or engineer and auditor checks, review any unfamiliar dependency. These paths come from canonical depends_on relationships; Web3 Academy does not track completed lessons.

Review 7 dependencies

• AssetRequired through Asset versus claim

  1. Vault
  2. Fee
  3. Asset versus claim
  4. Asset

• ClaimRequired through Asset versus claim

  1. Vault
  2. Fee
  3. Asset versus claim
  4. Claim

• TokenRequired through Asset versus claim

  1. Vault
  2. Fee
  3. Asset versus claim
  4. Token

• Asset versus claimRequired through Fee

  1. Vault
  2. Fee
  3. Asset versus claim

• FeeDirect prerequisite

  1. Vault
  2. Fee

• Net asset valueDirect prerequisite

  1. Vault
  2. Net asset value

• StrategyDirect prerequisite

  1. Vault
  2. Strategy

A vault is an on-chain asset container that accepts or controls assets, applies accounting and access rules, and may deploy capital through one or more strategies.

Category: Products and vaultsContainer outline category cue

System record

Start with the economic purpose, participants, resources, and entitlements before studying implementation detail.

Why it exists

Vaults package custody, share accounting, strategy execution, fees, limits, and redemptions behind a reusable interface so users can hold one claim instead of operating every position.

Traditional-finance analogy

Managed account or pooled investment vehicle is the closest comparison recorded for this concept.

Where the analogy stops

• A vault is contract infrastructure and does not by itself establish a regulated fund, fiduciary duty, legal ownership structure, custody protection, or investor rights.
• Code can automate accounting and execution, but governance, keepers, oracles, integrations, upgrades, and emergency powers remain control dependencies.

Main actors

• ActorDepositor or shareholder
• ActorVault contract
• ActorStrategy manager, allocator, or keeper
• ActorUnderlying protocols and counterparties
• ActorFee recipient
• ActorGovernance, guardian, or upgrade authority

Assets and claims

Assets — controlled or transformed resources

Assets are resources the mechanism moves, holds, values, or transforms.

• AssetDeposited underlying assets
• AssetIdle cash and deployed positions
• AssetEarned assets and reserves

Claims — entitlements and corresponding dependencies

Claims are rights to value, repayment, redemption, control, or another party's performance; each depends on an obligation or system that must honor it.

• ClaimVault-share or account entitlement
• ClaimPending deposit or withdrawal claim
• ClaimUnderlying strategy claims, debts, and fee liabilities

A vault is an on-chain container that controls assets, accounting, access, and possibly one or more strategies.

Why it exists

Users can hold one vault claim instead of repeatedly operating every lending, staking, liquidity, or hedging position themselves. The vault packages deposits, share accounting, allocation, fees, limits, reporting, and exits. That convenience concentrates dependencies rather than eliminating them.

Traditional-finance analogy

A managed account or pooled investment vehicle is a useful analogy. A smart contract vault does not by itself establish a regulated fund, legal entity, fiduciary duty, protected custody arrangement, disclosure regime, or investor remedy. Its code can automate rules while governance, keepers, oracles, adapters, and upgrades retain control.

Vault, fund, strategy, and asset

Table: Vault, fund, strategy, and asset

Term	Role	Important boundary
Underlying asset	Unit accepted, managed, or valued	Not the same as the vault share
Strategy	Operations intended to pursue an outcome	Can exist without a vault
Vault	Technical container and accounting system	Can be passive or manage several strategies
Fund	Broader pooled product and operating terms	May include legal and off-chain relationships
Vault share	Holder claim under vault accounting	Value and liquidity depend on the whole system

Step-by-step lifecycle

1. Admit an eligible asset under deposit caps, allowlists, recipient rules, and current valuation.
2. Transfer assets and mint a vault claim using pre-operation accounting and disclosed rounding.
3. Keep required liquidity and allocate only approved amounts to strategies or adapters.
4. Record every received claim, debt, reward, fee, pending operation, and impairment.
5. Report profit and loss without treating deposits, withdrawals, or token donations as income.
6. Rebalance or unwind within authorization, oracle, slippage, debt, and loss limits.
7. Burn or lock shares and transfer, reserve, or queue the holder’s eligible assets.

Balance sheet and flows

Table: Balance sheet and flows

Vault assets	Vault liabilities and claims
Idle underlying and reserves	Outstanding vault shares
Deployed strategy positions	Pending withdrawals and redemptions
Accrued income and receivables	Borrowed assets and financing costs
Recoverable collateral or claims	Accrued fees and impaired obligations

Capital flow connects deposits, strategy deployment, income, fees, repayment, and withdrawals. Claim flow connects shares, underlying protocol positions, debt, and queues. Return flow starts with named borrowers, traders, networks, services, asset issuers, or incentives. Risk flow reaches shareholders through every strategy, oracle, control, and liquidity dependency.

NAV and share accounting

vaultNAV = recognizedAssets - recognizedLiabilities
shareValue = vaultNAV / eligibleShareSupply

This is an accounting model, not a promise of immediate liquidity. Each vault must define recognition, timestamps, prices, fees, pending claims, impairment, and whether previews or withdrawals can execute at the modeled value.

Return source and loss allocation

The vault wrapper creates no return. Underlying positions earn borrower interest, trader fees, network issuance, service payments, asset income, incentives, or price changes. Costs and fees reduce that result. Unless an explicit reserve, insurance policy, manager guarantee, or subordinated class intervenes, loss reduces the value available to vault-share holders.

Engineer or auditor lens

Reconcile controlled assets, strategy debt, claim tokens, liabilities, reserves, fees, pending deposits and withdrawals, and total share supply. Test first and last user, donation and inflation attacks, rounding, unusual tokens, reentrancy, partial strategy withdrawals, loss reports, locked profit, stale oracles, keeper races, allocation limits, paused states, emergency exits, upgrades, allowance scope, fee changes, and residual assets after shutdown.

ERC-4626 standardizes one single-asset tokenized-vault interface while explicitly leaving allocation and accounting implementation details to each vault. Interface compatibility is not a security, solvency, liquidity, or performance certification.

Common misunderstandings

• “A vault removes complexity.” It moves complexity behind one claim and concentrates it in accounting, integrations, and control.
• “Assets in the vault contract equal all vault assets.” Capital can be deployed, borrowed, queued, impaired, or represented by claims.
• “Standardized vault means safe vault.” An interface says how to call a product, not whether its strategy or controls are sound.

Inspect the holder’s vault share, the broader fund boundary, and ERC-4626.

Machine-readable model

Key equations

Canonical expressions come from the structured concept record. KaTeX renders the notation, while the plain-text expression and variable table keep its meaning and units inspectable without JavaScript. Read the narrative above for the model's domain, assumptions, and rounding rules.

This concept does not require one canonical equation. Its mechanism and state transitions remain the authoritative explanation; do not invent a formula merely to make the topic look quantitative.

Interactive module

Test the mechanism

Change assets, shares, return, fees, deposits, and withdrawals; inspect NAV, ownership, and dilution.

Open Vault share-accounting lab on its full lab page

Accounting inputs

Controls

Existing assets

Unit: USD · Must be greater than or equal to 0

USD

Underlying asset value already controlled by the vault.

Existing shares

Unit: shares · Must be greater than or equal to 0

shares

Outstanding claims held before this accounting transition.

New deposit

Unit: USD · Must be greater than or equal to 0

USD

Fresh underlying asset value entering after fees are priced.

Profit or loss

Unit: USD · Signed; loss cannot exceed assets

USD

External strategy result applied before fees; use a minus sign for loss.

Management fee

Unit: % / year · 0% through 100%

% / year

Annual rate applied over this lab's fixed one-year accounting period.

Performance fee

Unit: % · 0% through 100%

%

Rate applied to positive period profit; no high-water mark is modeled.

Withdrawal shares

Unit: shares · Cannot exceed new shares minted

shares

New depositor shares burned after the deposit transition.

Reset allShare current state

Current transition

Claims follow assets

The strategy adds $50,000.00 to assets before fees. The vault mints 1,498.308362 fee shares and 9,666.505558 depositor shares. Burning 5,000.000000 depositor shares returns $51,725.00; final NAV is $1,098,275.00.

Final NAV

$1,098,275.00

Share price

$10.345000

New shares

9,666.505558

Accounting ledger

Results

Vault results. Display values are rounded; calculations retain Decimal precision.

Metric	Value	Unit	Meaning
Opening NAV	1,000,000.00	USD	Existing underlying assets at the start of the transition
Profit or loss	+$50,000.00	USD	Exogenous strategy result applied before fees
NAV after profit or loss	1,050,000.00	USD	Asset value before fee-share minting
Management fee value	10,500.00	USD	Annual rate applied for the fixed one-year accounting period
Performance fee value	5,000.00	USD	Rate applied only to positive profit in this model
Fee shares minted	1,498.308362	VAULT-SHARE	Claim issued to the fee recipient instead of assets removed
New depositor shares minted	9,666.505558	VAULT-SHARE	Deposit value divided by the post-fee share price
Depositor ownership after deposit	8.70	percent	New shares divided by total post-deposit shares
Withdrawal value	51,725.00	USD	Underlying value transferred for burned depositor shares
Final NAV	1,098,275.00	USD	Assets remaining after the withdrawal settles
Final share price	$10.345000	USD per VAULT-SHARE	Final NAV divided by final outstanding shares
Depositor ownership after withdrawal	4.40	percent	Remaining depositor shares divided by final total shares

Accounting sequence

State transition

Assets move first; share claims are then minted or burned against the current share price.

The vault moves from $1,000,000.00 and 100,000 shares to $1,098,275.00 and 106,164.8139 shares. The new depositor finishes with 4.40% ownership.

Vault accounting state transitionFive stages show opening state, profit or loss, fee-share minting, deposit, and withdrawal. A complete data table follows.

Inspectable alternative to the state-transition diagram. Display values are rounded; calculations retain Decimal precision.

Stage	NAV	Total shares	Share price	State change
Opening state	$1,000,000.00	100,000	$10.0000	Existing assets and outstanding claims enter the period.
Profit or loss applied	$1,050,000.00	100,000	$10.5000	Strategy return changes assets; the share count is unchanged.
Fee shares minted	$1,050,000.00	101,498.3084	$10.3450	Fee claims dilute existing owners without removing vault assets.
Deposit accepted	$1,150,000.00	111,164.8139	$10.3450	Underlying assets enter and priced vault shares are minted.
Withdrawal settled	$1,098,275.00	106,164.8139	$10.3450	Vault shares burn and proportional underlying value exits.

Claim composition

Ownership and dilution

Pattern, label, and position identify each owner; color is supplementary.

• Existing shareholders
• Fee recipient
• New depositor

Before feesExisting shareholders own the pre-transition share supply.

After fee sharesThe fee recipient owns 1.4762% after fee shares are minted.

After depositThe new depositor owns 8.6957% before withdrawing.

After withdrawalThe new depositor retains 4.3955% after burning shares.

Ownership percentages at every dilution stage. Zero-percent owners remain listed so the claim structure is explicit.

Stage	Owner	Ownership
Before fees	Existing shareholders	100%
Before fees	Fee recipient	0%
Before fees	New depositor	0%
After fee shares	Existing shareholders	98.5238%
After fee shares	Fee recipient	1.4762%
After fee shares	New depositor	0%
After deposit	Existing shareholders	89.9565%
After deposit	Fee recipient	1.3478%
After deposit	New depositor	8.6957%
After withdrawal	Existing shareholders	94.1932%
After withdrawal	Fee recipient	1.4113%
After withdrawal	New depositor	4.3955%

Balance-sheet view

Dilution ledger

Every row totals 100% when shares exist; an empty vault totals 0%.

Ownership claim percentages before and after each share-supply transition.

Stage	Existing owners	Fee recipient	New depositor	Total
Before fees	100%	0%	0%	100%
After fees	98.5238%	1.4762%	0%	100%
After deposit	89.9565%	1.3478%	8.6957%	100%
After withdrawal	94.1932%	1.4113%	4.3955%	100%

Guided comparison

Guided scenarios

Compare first deposit, positive return, and loss accounting.

1. 01Profit, fees, and withdrawalFollow value through profit, fee-share dilution, a new deposit, and a partial withdrawal without changing the underlying share price mechanically.
2. 02First depositorStart an empty vault under the documented one-dollar initial share-price convention and inspect who owns the resulting shares.
3. 03Loss, then fresh capitalObserve a loss reducing NAV and share price, a zero performance fee, and a new depositor receiving more shares per contributed dollar.

Terms in this model

Separate the system from its claims

Vault

The onchain accounting container that holds assets and issues shares.

Fund

The broader pooled investment arrangement; it may include legal and operational layers outside this vault.

Strategy

The activities that deploy underlying assets and create profit or loss.

Underlying asset

The economic value controlled by the vault and transferred on deposit or withdrawal.

Vault share

A proportional claim on vault NAV, not a fixed claim on a fixed quantity of assets.

NAV

Net asset value: the modeled USD value of assets remaining under vault control.

Return source

The strategy's counterparties or economic activities pay gains; depositors and fee minting do not create return by themselves.

Loss absorber

Shareholders absorb strategy loss through a lower NAV and share price.

The lab treats strategy profit or loss as an external input. It does not model a specific protocol, high-water mark, locked profit, streaming fee checkpoint, asset decimals, oracle, or transaction ordering attack.

Assurance contract

Security properties

These structured statements define desired behavior. Their stable IDs can bind tests, invariants, specifications, audit findings, or proof results without turning descriptive review advice into an assurance claim.

Desired · not evaluated: No test, audit, or proof result is implied until scoped evidence is linked to this property.

1. SP-01Desired · not evaluated

   Controlled assets, deployed positions, liabilities, fees, reserves, queued claims, and share supply reconcile across every state transition

2. SP-02Desired · not evaluated

   Deposits and mints cannot receive too few shares, and withdrawals and redemptions cannot transfer excess assets, outside explicit slippage and rounding rules

3. SP-03Desired · not evaluated

   Strategy allocations, debt limits, allowed assets, counterparties, and privileged operations remain authorized and bounded

4. SP-04Desired · not evaluated

   Pauses, emergency exits, upgrades, reports, fee changes, and recovery paths cannot silently rewrite existing holder entitlements

Prerequisites

Direct dependencies recorded by this concept's canonicaldepends_on relationships.

• FeePath 9

  A fee transfers assets, shares, or economic value from users or a product to a named recipient under an explicit charging base, rate, time rule, and settlement method.

• Net asset valuePath 36

  Net asset value is the value of a product's recognized assets minus its recognized liabilities at a stated valuation time and in a stated reporting unit.

• StrategyPath 37

  A strategy is an ordered set of financial operations, controls, and rebalancing rules intended to produce a stated outcome from underlying assets and primitives.

Learn next

Concepts that directly depend on this one, ranked by the recommended learning path. Check each page for additional prerequisites.

• ERC-4626 tokenized vaultPath 69

  ERC-4626 standardizes an ERC-20 share interface for vaults that accept one underlying ERC-20 asset, while leaving strategy, valuation, controls, and safety to each implementation.

Knowledge check

Quiz

Answer in your own words, then open the model answer.

What problem does Vault exist to address?

Model answer

Vaults package custody, share accounting, strategy execution, fees, limits, and redemptions behind a reusable interface so users can hold one claim instead of operating every position.

Mark as understood