Part of the flotation will be by auction (see article).
The flotation will raise about £890m that Worldpay will use to reduce its debt.
The flotation will happen just a few days after Poland and seven other post-communist countries join the European Union.
The flotation will change MasterCard from an association owned by thousands of member banks into a more transparent, listed company.
The flotation will provide some much-needed cash to Visa's shareholders, the banks that issue credit cards.Siemens issued a surprise profit warning because of delays to projects and contract cancellations, which will drag down its quarterly earnings by euro900m ($1.4 billion).
The exact size of the flotation will depend on investor appetite, but at least 41% will be sold on top of the 10% handed to postal workers.
The flotation will raise $21.8 billion, narrowly missing the record for the world's biggest stock offering, held by Agricultural Bank of China with its $22.1 billion listing in 2010.
Silicon Valley insiders and those close to the company doubt the flotation will change Facebook much.
The Co-op Group, whish is expected to have a majority stake in the bank after its flotation, will have its chief executive Euan Sutherland on the bank board.
The flotation vest will pin you to the bottom of the boat, and it'll be hard to push off or roll out from under it.
