Honeywell does not seem to have got the memo that conglomerates have become achingly unfashionable. At a time when the global trend is for industrial empires to break up and generate returns by specialising in a single area of business, boss Vimal Kapur has been bulking up.

The activist investor, which has amassed a $5 billion stake, is calling for big changes. Honeywell shares were up about 5% on the news.

Activist investor Elliott Investment Management called for a break-up of Honeywell into its aerospace and automation businesses on Tuesday, after saying it had built a stake worth more than $5 billion in the industrial giant.