Optimiser meaning

In legal practice, an optimiser is software (or an algorithm within investment software) used by investment managers and advisers to build portfolios by generating an “efficient frontier” from specified input assumptions and constraints. It typically takes inputs such as expected returns, volatility, correlations, risk measures, transaction costs, liquidity limits and mandate or regulatory constraints (for example, concentration limits, prohibited assets or ESG screens), and outputs proposed asset weightings that maximise expected return for a stated level of risk, or minimise risk for a target return. The term is descriptive rather than a defined term in legislation or case law in England and Wales, Scotland, Northern Ireland or Ireland, and usage is broadly consistent across these jurisdictions (US spelling: optimizer). Optimisers are commonly referenced in investment management agreements, pension scheme Statements of Investment Principles, fund prospectuses and investment policy statements to support asset allocation, mean-variance optimisation and liability-driven or strategic asset allocation decisions. Legal significance includes: documenting the assumptions and constraints used; acknowledging model risk and that outputs do not guarantee performance; and ensuring suitability, governance and disclosure obligations are met. Contracts may include limitations of reliance, warranties about data inputs, and compliance with applicable regulatory requirements when using optimiser outputs.