How NULL compares
Against wallets, custodians and mixers.
NULL gets compared to three things, and it's genuinely different from all of them. The differences are structural rather than a matter of degree, which is why they're worth going through properly.
Versus a wallet
A wallet holds tokens you own. That's the entire difference, and everything else follows.
| Wallet | NULL | |
|---|---|---|
| You hold | Tokens | Spending rights |
| Key stolen | Everything in it | Outstanding rights, capped |
| Public | Balance and full history | Reserve activity, nobody's in particular |
| Can you hold a position? | Yes | No, deliberately |
If holding is what you want, a wallet is better and NULL isn't trying to replace it.
Versus an exchange or custodian
These look similar at first, since in neither case are you holding the tokens yourself. The difference is what sits between you and the money.
A custodian keeps a balance in your name and applies its own rules, which it can change, and which it can be made to change by someone else. A reserve keeps no balance for anyone, and the rules are enforced by the protocol.
The fair caveat: automatic enforcement doesn't mean nobody wrote the rules. Who writes reserve policy is a real question, and Reserve policy doesn't dodge it.
Versus a mixer
This is the comparison that matters most, because it's the first thing people reach for and it's where the difference is sharpest.
A mixer takes coins you already own and works to obscure where they went. Three things are true of that: you owned them, a trail got created, and work happens afterwards to break the link. That last step is what attracts attention, because obscuring a trail is a deliberate act taken after the fact.
NULL does none of it. The money is never assigned to you, so no trail is created, so there's nothing to break. The privacy isn't something done to a record. It's the absence of the record.
One breaks a link, the other never makes one. A mixer needs a step whose job is covering tracks, and that step is what draws attention. NULL has no equivalent step, because the money was never yours to leave a trail behind.
One question makes it obvious: what would you have to delete to make this system stop being private? For a mixer, the mixing step. For NULL, nothing, because nothing was written down in the first place.
That's a statement about how it's built, not a legal opinion, and it shouldn't be read as one.