Docs

Borrower. Lists a card with a loan, a payback amount and a term. Gets USDC when the listing is funded.

Depositor. Puts USDC into the vault, receives vault shares and earns the fixed costs borrowers pay.

Direct lender. Funds a single listing in full from their own wallet, receives the payback, or the card if it is not repaid.

Curator. A bot run by the Trainer Bank team that decides which listings the vault funds, within limits the contract enforces. Every decision is published on the Transparency page.

Keeper. A bot that starts sales and lowers prices on time. It only saves effort: anyone can send the same transactions.

Collector Crypt. Stores the physical card, issues the token, sets insured values and runs the marketplace where defaulted cards are sold. Trainer Bank is not affiliated with or endorsed by Collector Crypt.

At launch the vault funds Pokémon cards only, with these conditions:

1. Insured value between 50 and 25,000 USDC.
2. Held in Collector Crypt's vault for at least 45 days. New arrivals are usually revalued in their fifth week, sometimes by a lot.
3. Not frozen, and not listed for sale (if it is listed, the listing is cancelled in the same transaction that moves the card to escrow).
4. The loan is at least 10 USDC.

The curator starts from the insured value. If Collector Crypt is offering to buy the card back, the value is capped so that the buyback offer is at least 85% of it.

The value is locked at funding. If Collector Crypt later cuts or raises the insured value, an open loan is not affected.

Each card falls into one of three groups. The group sets the share of the value the vault lends. A direct lender can agree to any amount.

A card whose insured value rose more than 15% in the last 30 days moves down one group, or is not funded. Whatever the group, the contract never lets a loan exceed 60% of the value.

You choose the fixed cost when you list. The vault funds a listing only if the cost is at least its minimum, the same for every group. A listing below that can still be funded by a direct lender.

The 1% protocol fee is taken once, from the loan, when it is funded. It goes to the protocol, not to the lender, and it is the same for vault and direct loans. Nothing else is charged: early repayment costs the same payback, and there are no late fees because late payment is not possible.

To compare with yearly rates, multiply by the number of terms in a year. This is a comparison only; you pay the fixed cost once.

For a vault loan, the payback cannot be set so high that it would lift the lowest sale price. The second floor of a sale is 110% of the payback and it must not exceed the first floor, 58% of the value:

For a 500 card that is a payback of at most 263.63. Without this rule a borrower could pick a huge payback, default on purpose and keep the card off the market. Direct loans are not sold, so the rule does not apply to them.

1. 01
   Listing. The card moves to an escrow account owned by the protocol. The listing waits up to 24 hours. You can cancel at any time; if nobody funds it, anyone can return the card to you.
2. 02
   Funding. The vault, or a direct lender, pays the loan in one transaction: 1% to the protocol, the rest to your wallet. The deadline is set: funding time plus 7 or 21 days.
3. 03
   During the term. The card is locked. Nobody, including you and the team, can move it. Reminders arrive 72, 24 and 2 hours before the deadline.
4. 04
   Repayment. Pay the payback amount at any moment before the deadline and the card returns in the same transaction. If Collector Crypt has frozen the card, your payment is still accepted and the card is delivered once it is unfrozen.
5. 05
   Deadline. Repayment closes the second the deadline passes. There is no grace period: a vault loan's card goes on sale, a direct loan's card goes to the lender.

A PSA 9 card from 2016 (group B) with an insured value of 500, borrowed from the vault for 7 days at the full limit and the vault's minimum cost.

The fee is charged once per loan, so it weighs more on short loans. If you need the money for three weeks, one 21-day loan (11.00) costs much less than three 7-day loans (18.00).

The price is a share of the value at funding and depends only on the time since the sale started. It never goes up.

Floor 2 is always at least as low as floor 1, thanks to the payback ceiling above. It lets a card that will not sell at 58% find a buyer, while the vault still never sells for less than 110% of what it is owed.

If a card does not sell even at floor 2, it stays listed at that price. In the vault's books it is written down, see Defaults and write-downs.

Buyers on Collector Crypt also place offers. Anyone can accept an offer for a defaulted card once it is at least the current price:

Because the price falls every hour after 12 h, a waiting offer is accepted as soon as the schedule reaches it: an 85% offer at hour 12, an 80% offer at hour 15, a 70% offer at hour 19. The buyer pays the offer amount.

There is no discount for offers below the price. Since acceptance is open to anyone, a discount would let any buyer place and accept a cheaper offer in one transaction.

Collector Crypt keeps a 2% fee on every marketplace sale. The vault receives the rest:

If the marketplace stops working for these cards (paused, card no longer accepted, program changed), a fallback opens after 1 hour, or after 1 day in every case. Anyone can then buy the card directly from the protocol at the same scheduled price. The 2% royalty is paid there instead, so the vault receives the same amount either way.

The card from the borrowing example is not repaid: value 500, payback 204.00.

Even the lowest sale returns more than the payback. The vault loses money on a default only if the card cannot sell at floor 2, or if Collector Crypt moves or burns it.

The lender sees the listing's loan, payback and term, and pays the loan in one transaction. If the borrower changed the listing in the meantime, the transaction fails, so a lender never funds terms they did not see.

The vault's minimum cost and lending limits do not apply: the lender decides whether the card is worth the loan. A listing can be funded by the vault or by one lender, never both.

The borrower repays exactly as with a vault loan, at any time before the deadline. The payback first lands in an account that belongs to the loan itself, then goes to the lender, usually in the same transaction.

Because the payback never depends on the lender's own account, a lender cannot block a repayment to keep the card, for example by closing their USDC account.

At the deadline the card moves to the lender's wallet. Anyone can send that transaction; the card can only go to the lender. There is no sale, no price schedule and no surplus: the lender keeps the card whatever it is worth.

If Collector Crypt has frozen the card, it moves once unfrozen. If Collector Crypt has moved or burned it, the loan closes and the lender gets nothing.

The same 500 card, listed below the vault minimum: a loan of 200 for 7 days at a fixed cost of 1.5%. The vault will not fund it; a direct lender does.

Depositors own shares of the vault. The vault's net asset value (NAV) counts everything it owns:

Rounding always favours the vault, so no deposit or withdrawal can take value from the others.

Each loan's fixed cost enters the NAV second by second over its term, not in one jump at repayment, and already net of the 10% performance fee, so recording a loan repaid on time does not move the share price:

Someone who deposits the day before a big repayment therefore pays a share price that already includes most of that yield, and cannot grab it.

When a loan is repaid, the payback joins idle cash and the protocol keeps a performance fee of 10% of the realised yield:

If a borrower repays early, the yield that has not accrued yet keeps entering the NAV on the original schedule, up to the original deadline. An early repayment never makes the share price jump.

When a loan defaults, its book value stays at the loan plus the yield after the fee while the card is for sale, because even floor 2 returns more than that:

When the card sells, the amount received replaces the book value. A shortfall shows up in the share price at once; a gain is added over 3 days (next section). If the card is still unsold 7 days after the deadline, its book value is written down in a straight line to zero over the next 30 days; a later sale writes the real amount back.

If Collector Crypt moves or burns the card, the book value drops to zero at once. Collector Crypt can freeze, move and burn the cards it issues.

A card usually sells for more than the payback, so a sale lifts the NAV. If that gain landed in one moment, someone could deposit just before it, wait for the sale to be recorded, and withdraw straight after, taking part of a gain that belongs to the depositors who carried the loan. To stop that, any gain above the book value is added to the NAV in equal parts over 3 days:

The cash itself is in the vault at once and can pay withdrawals; only the price waits. Someone who wants a share of the gain has to stay in the vault for those 3 days and carry the same risk as everyone else. A deposit made during those 3 days pays the full share price, including the part still locked, so it cannot take a share of it; a withdrawal before the unlock ends leaves that part to the depositors who stay. Losses are never delayed.

Withdrawals are paid from idle cash. If there is not enough, the rest joins a first-in, first-out queue and is paid as loans are repaid or cards are sold. Cash goes to depositors first: while someone is waiting, the vault funds a new loan or pays an instant withdrawal only if the cash left still covers everyone in the queue.

The vault funds the 7-day loan from the borrowing example and it is repaid.

The vault's overall return is roughly this rate times utilisation, minus losses from defaults. If half the vault is lent at this rate, the per-year equivalent is about 1.80% × 365 ÷ 7 × 50% ≈ 47%. That is arithmetic, not a forecast: rates, utilisation and defaults all change.

Parameter changes take effect only after a 48-hour time lock, and never change loans that are already open.

The LTVs come from what sellers actually received on Collector Crypt, divided by the insured value. In the week of 16–23 October 2026 (5,309 sales by sellers other than Collector Crypt) the median was 0.90 and the worst 10% sold below 0.805; in earlier weeks that worst-10% mark was 0.70–0.73.

The rule keeps a 30% cushion under the weakest recent result:

With ratios of 0.70–0.80 that allows 49–56%; the vault's groups sit at 25–45%. The rest of the gap covers insured values that are cut after funding (a cut of 25% or more within 30 days happens to 7–11% of cards).

1. A card whose insured value rose more than 15% in 30 days moves down a group or is not funded: about a fifth of value cuts undo a rise from the month before.
2. If the monthly median sale ratio falls two months in a row, every group's LTV is cut by 5 points.
3. No more than 25% of the vault goes into one set or category.

The contract reads no prices. Values, groups and sale profiles are decided off-chain by the curator. What the contract guarantees:

1. The loan, payback and deadline cannot change once funded.
2. A card leaves escrow only to its borrower after repayment, to a buyer through a sale (vault loans), or to the direct lender after a missed deadline. Nobody, including the team, can take it.
3. The sale price follows the schedule and never goes below the floor; the second floor is always 110% of the payback.
4. Vault loans stay within the curator limits: at most 60% LTV, the minimum fixed cost, the per-card, per-borrower and daily caps.
5. Starting a sale, lowering the price, accepting an offer and settling are open to anyone. If every Trainer Bank server stopped, borrowers could still repay and depositors could still withdraw.

The contracts are not audited yet. Read the Risks page before you borrow or deposit.