Sizing per name: from risk to shares

Three tracks divided a budget by a per-contract risk. Equities does the same division, and the answer arrives already denominated in shares.

The chain, one unit long

Each share loses exactly the stop distance across the stop - no multiplier, no lookup, no currency leg on a domestic name. Cash at risk divided by stop distance is the share count, full stop. Work the example: the whole machine that took three lessons of commodity plumbing runs here in one line - which is exactly why it gets skipped, and why this lesson exists to make skipping it feel as wrong as it is.

What equities changes about the mechanics

• The floor rarely bites: fractional shares mean the computed size is usually the held size - the whole-contract compromises of other tracks mostly vanish, and with them the under-budget slack.
• Position value falls out free: shares times price - and it feeds the per-name cap lesson 6 adds, the second constraint equity sizing carries.
• Expensive shares change nothing: a four-figure share price just means fewer shares for the same risk - the division does not care, and neither should the trader.

The two-constraint preview

Equity sizing answers to two masters: the risk budget against the stop - this lesson - and the concentration cap against the name, lesson 6's subject, because a stop cannot price the overnight halving. The final size is the smaller of the two answers. That second constraint is new to this track, it exists because ownership concentrates in a way derivative baskets did not, and it is where equity sizing stops being merely the easiest version of the platform's arithmetic.