Tidying my drawers this week, I found some research notes I wrote in the late 1990s. It was my last job in stockbroking — I was an internet stock analyst at a time when technology, media and telecoms (TMT) shares were shooting skywards. 

By 2000, commentators were screaming “bubble”. That April my firm, Dresdner Kleinwort, alongside Goldman Sachs, led the IPO of Deutsche Telekom internet subsidiary T-Online. The market was jittery. Remarkably, the T-Online IPO got away successfully — its shares rising more than 40 per cent at the end of the first day. It was probably the last to do so. The “tech wreck” was already under way.

As talk of bubbles in artificial intelligence (AI) stocks grows, there are some lessons to apply from those years. Chief among these is not to throw the baby out with the bathwater.