Wells Fargo Investments invests more than $1 trillion a year.
Including the $2.4 trillion the bank holds in the US stock market, Wells Fargo has an investment portfolio of $1.8 trillion, according to the US Securities and Exchange Commission.
Its largest asset is its $1,600-a-year mortgage insurance business.
For the past six years, Wells has been the biggest holder of the Dow Jones Industrial Average index, with a record $4.7 trillion in the form of short-term, index-linked investments.
It also holds $1 billion in equities and $2 billion in bonds, according a Wells Fargo spokesperson.
“We are a firm believer that equity markets are a wonderful way to invest,” said Jim McBride, Wells’ chief investment officer.
Wells Fargo invests a significant amount in private companies, which in turn are invested in the broader economy, McBride said.
The bank invests in US businesses, and has more than 1,000 corporate employees, including over 1,500 retail and wholesale associates.
But, its biggest asset is Wells Fargo’s mortgage insurance portfolio, with $1bn in mortgages, according the SEC.
This is the fourth time that Wells Fargo Investment Services has topped the Dow.
At the time of writing, Wells was up nearly 6 per cent.
Investors have been snapping up Wells Fargo bonds and other investments, particularly in the energy sector.
Over the past five years, the Dow has soared almost 400 per cent, with the latest jump in November of nearly 7 per cent the biggest gain since August 2007.
While the Dow is on track to its highest level in a decade, the US equity market is still experiencing a boom.
More than 1.5 million companies and investments have jumped in value over the past year.