Commingling
Commingling is the mixing of client assets with each other, or with a custodian's own assets, to the point that individual ownership can no longer be traced, which is what lets a court treat those assets as property of the custodian's bankruptcy estate.
Commingling describes the mixing of one client's assets with those of other clients, or with the custodian's own holdings, in a single pool. In bitcoin custody it typically means client coins are held in shared "omnibus" wallets rather than in dedicated, per-client addresses. Operationally, commingling is convenient. Legally, it is the condition under which client ownership dissolves when a custodian fails.
The Prime Trust bankruptcy made the consequence concrete. One customer argued that the transparency of the bitcoin protocol, specifically the unspent-transaction-output model, made its holdings traceable on-chain and therefore identifiable. The court rejected the argument, finding the assets so thoroughly commingled as a legal matter that even theoretically traceable bitcoin could not be attributed to individual customers. The chain may record whose coins are whose; the bankruptcy court decided it did not matter. Protocol-level transparency does not survive custody-level commingling and a court's reading of it.
Commingling is invisible in most day-to-day disclosures. A reserve attestation can show that a custodian holds enough bitcoin in aggregate while saying nothing about whether any of it is segregated to you. That is why the question of segregation matters more than the question of reserves.
The structural answer is to remove commingling entirely. In Onramp's Multi-Institution Custody, each client's bitcoin sits in a segregated vault rather than a pooled account, and no single institution ever holds the keys alone, so client assets cannot be blended into a custodian's estate.
Related reading
Commingling is the mixing of client assets with each other, or with a custodian's own assets, until individual ownership can no longer be traced. In the Prime Trust bankruptcy a court held that commingled client bitcoin was property of the estate, even though bitcoin is traceable on-chain. Onramp's Multi-Institution Custody eliminates commingling by holding each client's bitcoin in a segregated vault that no single institution controls.
Frequently Asked Questions
What is commingling in bitcoin custody?
It is the mixing of one client's coins with those of other clients, or with the custodian's own holdings, in a single pool, typically a shared omnibus wallet rather than dedicated per-client addresses. It is convenient operationally and dangerous legally.
Does bitcoin's traceability protect against commingling?
No. In the Prime Trust case the court found the assets so thoroughly commingled as a legal matter that even theoretically traceable bitcoin could not be attributed to individual customers. Protocol transparency does not survive custody-level commingling.
Why does commingling matter more than reserves?
A reserve attestation can show a custodian holds enough bitcoin in aggregate while saying nothing about whether any of it is segregated to you. Segregation, not aggregate reserves, determines whether your assets survive a custodian's failure.
How does Onramp prevent commingling?
In Onramp's Multi-Institution Custody, each client's bitcoin sits in a segregated vault rather than a pooled account, and no single institution ever holds the keys alone, so client assets cannot be blended into any custodian's estate.