Software company Darktrace (DARK.L) is back in the FTSE 100(^FTSE), with house builder Vistry Group (VTY.L) and warehouse landlord LondonMetric Property (LMP.L) also getting promoted to the UK's blue-chip index.

Making room for these promotions were online supermarket Ocado (OCDO.L), which ended its six-year stay in the FTSE 100 on Wednesday night as the UK's blue-chip index undertook a reshuffle that also saw financial adviser St James Place (STJ.L) and electrical components maker RS Group (RS1.L) drop out.

The FTSE 100 is reshuffled by FTSE Russell, the index provider, every quarter according to market cap data from the end of the previous month.

The cybersecurity Darktrace firm has surged more than 71% over the year to date, giving it a market cap of £4.1bn. It marks its return to the FTSE 100 index for the first time since it was kicked off in December 2021.

This might not last long, however, as Darktrace was recently bought by US private equity firm Thoma Bravo in a £4.2bn deal.

“One of the indicative changes to the FTSE indices could be short-lived. Darktrace looks set to join the FTSE 100, but it is in the process of being acquired by Thoma Bravo, so could disappear from the top tier fairly soon," Dan Coatsworth, investment analyst at AJ Bell said.

Meanwhile, housebuilder Vistry has gained 38% to be valued at £4.2bn after being the best-performing housebuilder on the FTSE 250 (^FTMC) this year.

“Trading has been good for the company, having guided a fortnight ago for half-year and full-year profit to be ahead of last year," Coatsworth said.

“Investors like what they’re hearing and the shares have steadily ticked up since last October, with a 38% total return year-to-date. That makes Vistry the best-performing housebuilder in the mid-cap index and the 21st best-performing FTSE 350 stock so far in 2024."

The warehouse landlord LondonMetric Property has been promoted to the FTSE 100 for the first time, joining larger rival Segro as two of only three commercial property companies in London's blue-chip index.

"The reshuffle also involved demotion from the FTSE100 for St James’s Place and RS Group. The replacement promoted shares provided further proof of something of a revival in the property sector, with Vistry Group and LondonMetric Property being added to the index, as well as a final sprint which brought Darktrace over the line to regain its status after previous relegation in December 2021," Richard Hunter, head of markets at Interactive Investor, said.

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