In the last week, Microsoft has joined Apple as the only US companies to reach a $US3 trillion market valuation.

Just seven tech stocks - Apple, Microsoft, Alphabet, Amazon, Nvidia, Meta and Tesla - make up almost 30 percent of the S&P500.

So can they keep growing? Catriona Burns, Lead Portfolio Manager for WAM Global, talks to Sean Aylmer about what it mean for investors when so few companies make up such a large portion of the market.

This is general information only. You should seek professional advice before making investment decisions.