In the UK, I believe stock brokers are required to use nominee accounts to hold shares on behalf of individual investors, so that if the stock broker were to collapse the investments themselves are safe.
But in cases of fraudulent accounting or recklessness (i.e. Pritchard Stockbrokers), it is still possible to lose money when a stockbroker fails.
Do investors with large portfolios (6 or 7 figures or more) spread investments over multiple stockbrokers to mitigate this risk?
What about the actual funds? Is it a bad idea to invest large amounts in funds provided by a single company, e.g. Vanguard? Could you lose you money if a fund management company like this goes bankrupt?