Transaction Begin Message Fields

The Transaction Begin message indicates any subsequent messages, up to the accompanying Transaction End message, are all part of the same transaction block. All PITCH messages corresponding to such an event would be included between a Transaction Begin and Transaction End. It is important to note that any PITCH Message Type may be included in a transaction block and there is no guarantee that the messages apply to the same price level or even the same Symbol. Transaction Begin messages do not alter the book and can be ignored if messages are being used solely to build a book.

Feed processors can use a transaction block as a trigger to postpone publishing a quote update until the end of the transaction block.