Jupiter shares have opened at 190.25p on the first day of full trading on the London Stock Exchange, a 15% increase on its offer price.
The offer price of Jupiter's initial public offering was set 165p per ordinary share, but climbed sharply over the week of conditional trading.
Jupiter's IPO was more than 2.5 times oversubscribed after a strong take-up from both institutional and retail investors.
A number of Henderson fund managers bought into the IPO, taking a combined 2% stake in the group.
Graham Kitchen, who runs a number of equity products at the group, says the UK and European equity teams added the stock at the "very attractive" IPO price.
BlackRock also has a strong stake in Jupiter, buying a 5.13% share of the group.
"The success of the Offer is a tremendous achievement for Jupiter, particularly considering the ongoing volatility in global stock markets," Jupiter group chief executive Edward Bonham Carter says.
"The market for IPOs has been extremely difficult during this time and we are one of the few companies in Europe to have been able to proceed with a listing.
"I would like to take this opportunity to welcome our new shareholders as we embark on the next stage of the company's development."
At 9am, Jupiter's share price had dipped 0.66% to 189p.
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