Financial giants generally only downplay their size when it could cause problems. BlackRock is a case in point. Its assets grew 30 per cent to a record $9.5tn during the second quarter from a year earlier. Just five years ago, it managed a little over $5tn.

In an investor presentation last month, the world’s largest fund manager stressed that its revenue accounts for just 3 per cent of the industry’s global total. The suggestion is that BlackRock’s reach is negligible compared to titans in other sectors, such as cloud computing. Here, the top dog makes almost a third of overall industry revenue.

Yet BlackRock’s gigantism can only grow. Surging financial markets have pumped up its asset totals and emboldened investors to make new wagers via passive funds. iShares, BlackRock’s exchange traded fund business, sucked in $75bn — or 93 per cent of the group’s total net inflows — during the period.

Its ability to hoover up money highlights the advantages of scale in fund management. Vast size brings increasing huge economies of scale for the ETF whales, allowing them to reduce costs even further. New entrants have no chance of rivalling them.

Steady earnings growth has, meanwhile, made BlackRock a Wall Street darling. The shares are up 60 per cent during the past 12 months and have quintupled over 10 years. They fetch 23 times forward earnings, compared to 14 times for JPMorgan Chase and Morgan Stanley.

But BlackRock’s growing clout is bringing increased scrutiny. Critics say it holds too much sway via its share of proxy votes cast at S&P 500 companies. Regulators are asking whether mega fund managers should be deemed systemically important financial institutions — too big to fail in other words.

That would mean tighter regulation. BlackRock rightly argues that it manages money on behalf of clients, rather than putting its own capital at risk. Even so, it should get used to being in the regulatory limelight. The bigger BlackRock gets, the greater its gravitational pull on cost-conscious capital.

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