Fidelity, the US fund manager, is the most technologically innovative among its peers, research by the credit ratings agency Moody's suggests — and the best placed to defend its lucrative business against intrusion by the likes of Amazon or Google.

Moody's, which analyses asset managers' business models in order to gauge their ability to repay their debts, looked at the numbers of tech patents registered by fund companies. With 156 patents registered in the US since 1980, Fidelity is far ahead of its nearest rival Charles Schwab, a US wealth manager, which has 66.