Position limits are an identity problem · September 2026
Every event-market rulebook has a position limit. Almost none of them can answer the only question that makes a limit mean anything: limit per what? Per account, the answer is trivially gamed — a syndicate that wants 40× your limit opens 40 accounts. Per verified identity is better and still insufficient: family members, employees, and paid nominees each verify cleanly. The unit that matters is the operator — and operators are not declared. They're resolved.
The identifying exhaust of account operation is hard to fake at scale: funding sources, device fingerprints, network origin, addresses, and — for crypto-settled venues — wallet addresses. Treat each shared attribute as a weighted edge between accounts (a shared funding rail is near-conclusive; a shared apartment-building subnet is merely interesting), require weak edges to corroborate each other, and run connected components. What emerges is a cluster with a confidence score you can defend: not "these accounts feel related" but "joined by shared funding (0.9) and shared device (0.85); combined confidence 0.985."
Three controls change character at cluster level. Position limits become real: aggregate cluster exposure vs the limit — Core Principle 5's aggregation expectation, operationalized. Restricted-person checks become inheritable: one account on a roster list blocks the whole cluster — the trainer's-cousin problem, solved structurally. Insider detection gains its coordination signal: three "unrelated" accounts buying the same side in the same 20-second pre-news window is noise; three accounts from one resolved cluster doing it is CFTC 180.1 misappropriation with a diagram.
Resolution is probabilistic, so governance matters as much as graph theory. Clusters are proposals until a human confirms them; splitting one requires a documented reason and a second identity's approval; and re-resolution after new data preserves prior human validation instead of silently overwriting it. An entity-resolution system whose merges can't be challenged, audited, and reversed is a liability in the exact proceedings it exists to support.
Sports event contracts have put "who is really trading?" at the center of the Commission's attention — the leagues' letters are about insiders; the staff advisories are about surveillance capability. A venue that can show an examiner its operator graph, with weighted evidence and limits enforced at the cluster, is answering next year's exam question today. A venue enforcing limits per account is publishing the price of evading them: one KYC packet each.
DataTap's accounts path takes hashed funding tokens, never raw instruments — data & usage guide · for DCM applicants.