The universe rule

01 The rule at a glance

The universe is 119 instruments: 100 common stocks admitted by the rule below, plus 19 exchange-traded funds fixed in the rules. The rules are V1, effective 11 August 2026 — the date of the initial adoption refresh. Membership is recomputed quarterly, on the first of January, April, July and October; between refreshes it does not change.

02 Common stocks

Eligible instruments are US-listed common stocks. Share classes such as BRK.B are ordinary common stock and are kept; preferred shares, warrants, units, and rights are not common stock and are excluded.

Eligible stocks are ranked by median daily dollar volume — the median of close × volume per session — over the trailing 90 calendar days, requiring at least 45 sessions of data in that window. The last close must be above $5, and market capitalisation must be above $10B. The top 100 by that ranking are the universe's stocks, ranked 1–100.

03 The fixed ETF list

Nineteen ETFs, frozen in the rules:

Their dollar-volume statistics are recomputed at every refresh, but membership never changes under V1: changing this list is a versioned rules change, not a quarterly refresh.

04 Excluded from V1

Stated as discipline, not oversight:

05 The computable pipeline

Membership is decided by four steps anyone can run from public data:

06 Refresh cadence and change notice

The universe is recomputed on the first of January, April, July and October. Every refresh is exactly one commit to the public repository, recording the date and the added and removed tickers — the file's git history is the complete history of universe changes.

Per §11 of PROTOCOL.md, a universe change takes effect no earlier than one full cycle after the commit that introduces it, and every weekly manifest pins the universe file's hash — so a silent swap between weeks is detectable by any verifier.

07 One benchmark

SPY, for everything. The user-level question is always "did following this beat holding the index."

08 Check it yourself

The universe in force, its refresh history, and the change-notice guarantees are all public:

How the record itself is sealed, labeled, and spot-checked is the subject of the methodology page.