You've got to have these here in case you're ever playing divvies on the LSE....gotta know all about CUM and EX.
"The ex date divides the cum period from the ex period.
Bargains dealt prior to the ex date (during the cum period) are dealt with the benefit attached, unless stated to the contrary as a bargain condition."
Cum: Latin for 'with' (used in the abbreviations cum cap, cum div, cum rights, etc), to indicate that the buyer of a security is entitled to participate in the forthcoming capitalisation issue.
Cum all: A stock trading with the right to all supplementary advantages attached to the share. Cum capitalisation The purchaser of stock which is cum capitalisation is entitled to receive an issue of new shares made fully paid by the capitalisation of reserves and given free of charge in proportion to his or her existing holdings. Cum dividend The purchaser of a stock which is cum dividend is entitled to receive the declared dividend.
Cum period: A period during which a buyer of securities is entitled to the dividend regardless of whether or not he is on the register at the record date.
Cum rights: The purchaser of a stock trading cum rights is entitled to buy shares of a new issue of stock in direct proportion to his or her existing holdings.
Ex: The opposite of cum, and used to indicate that the buyer is not entitled to participate in whatever forthcoming event is specified (ex cap, ex dividend, ex rights, etc).
Ex all: The sale of a security without dividends, rights, warrants or other supplementary privileges associated with that security.
http://www.exchange-handbook.co.uk/index.cfm?section=glossary