Charlton Athletic raises for sale sign Thu 16 Aug, 04:21 PM LONDON (Reuters) - Charlton Athletic said it was up for sale on Thursday, joining a growing list of clubs changing ownership. Charlton, relegated from the Premier League last season, said it had retained boutique bank Seymour Pierce to consider a range of strategic options. A sale of the club, which owns some property, could fetch between 40 and 50 million pounds, a person close to the situation said. The club would also welcome a new investor to join existing shareholders, the source added. Billionaire investors from around the world have recently bought English football clubs to capitalize on growing TV and commercial revenue.