Wells Fargo, which has been making a push into investment banking since buying Wachovia in 2008, has now been rewarded with a role in one of the highest-profile flotations of the year.

The US bank - which is better known for its retail and commercial banking operations - is our investment bank of the week after making it as one of 11 banks to secure a place as a bookrunner on Groupon's long-awaited $700m initial public offering.