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Copy rules & sizing · updated 2026

The Max clamp and the blocked-instrument list

Two guardrails sit on top of your sizing: a per-follower Max and a global "Never copy these instruments" list. One caps quantity, the other removes whole markets from copying.

Max: a hard cap per follower

Every follower row on Copy Rules has a Max field. The app's own tooltip is the definition: the follower never holds more than this many contracts, whatever the sizing works out to. It defaults to 100 and must be a whole number, 1 or more — a save with less is refused: "Max must be a whole number of contracts, 1 or more."

The clamp is applied last, after the multiplier (or exact quantity) and after the Rev flip, and it works in both directions: a Max of 3 caps the follower at 3 long or 3 short. If a 10-lot leader trade at 1× meets a Max of 3, the follower holds 3. The clamp bounds the target — it does not skip the trade.

Set Max deliberately on small accounts. A multiplier typo is caught by the clamp; without it, the default 100 is doing very little for a 2-lot account.

Never copy these instruments

Below the group cards on Copy Rules sits the Copier settings card, marked "These apply to every group." Its "Never copy these instruments" field takes a comma-separated list of roots — for example CL,GC. A blocked root is not copied by any group, whichever leader trades it.

Use it when a follower's firm restricts certain products, or when you trade a market on the leader that you never want mirrored anywhere.

The block list is a structural setting. Changing it while the copier runs is refused — the whole Copy Rules editor locks with "Stop copying to edit these settings." Stop the copier, edit the list, save, and start again. See editing rules while the copier runs.

Quick answers

What happens when sizing exceeds Max?

The follower's target is clamped to Max, long or short. The trade still copies — at the capped size, never beyond it.

Does the block list apply per group?

No. It is global. A root in the list is never copied by any group.

Can I change Max or the block list mid-session?

No. Both are structural settings and require the copier stopped. Only the Follow switches and group renames work while it runs.

Next steps

Multipliers and exact quantity · Editing rules while the copier runs · Sizing for trailing drawdown

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© 2026 MirrorFill. Operated from the European Union. Trading futures involves substantial risk of loss and is not suitable for every investor. MirrorFill is a trade-copying tool, not a broker, financial adviser, or signal provider.