The Financial Conduct Authority (FCA) handed the fine to Invesco Perpetual, based in Henley-on-Thames, due to failings in its handling of risk.
The FCA said between May 2008 and November 2012 Invesco exceeded investment limits, designed to protect investors' exposure to losses. Invesco, the largest retail money manager in the UK, also did not tell investors it used financial derivatives, which increased the amount of risk the funds were exposed to.
The funds concerned lost £5m, although Invesco has fully compensated the losses and has since improved its controls and systems. The FCA warned the losses "could, however, have been greater".