PAMM (percentage allocation management module) and MAM (multi-account manager) accounts are structures that let one trader or money manager place trades that are allocated automatically across many investor accounts. In a PAMM setup investors contribute to a pool and each one's result is calculated as a percentage share of it. In a MAM setup the manager sends a block order that is split across linked sub-accounts by lot size or equity ratio, so each investor keeps an individual account. Investors normally pay the manager a performance fee, often measured against a high-water mark.
Operating such an account is usually treated as discretionary management, so licensing requirements, fee disclosure and reporting rules differ by jurisdiction.
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Account Types, and What Actually Changes Between Them
Standard, raw, cent, swap-free, professional. What genuinely differs between the tiers, and the one reclassification that costs you protections.