Whitbread, the leisure company that owns Costa Coffee and David Lloyd health clubs, is to be readmitted to the benchmark FTSE 100 stock index.
Joining the FTSE 100 can help boost a company's share price
The move is part of a reshuffle which happens every three months and is based on the market value of listed members.
Whitbread will replace nuclear power firm British Energy from 18 December.
The leisure company has seen its shares rise amid takeover speculation, while British Energy fell after it closed two reactors due to maintenance problems.
There also will be changes outside the FTSE 100, with Ashmore Group, Hochschild Mining, UK Commercial Property Trust, Daejan Holdings and UK Coal all due to join the FTSE 250.
They will replace Photo-Me International, Whatman, Wolfson Microelectronics, Computacenter and Kensington, which will be listed in the FTSE SmallCap index .