Ask Update Message Fields

Ask Update messages replace the previous Top of Book ask for a symbol. One Ask Update message may reflect one or more updates to the inside ask that were processed at the same time.

Table 1. Ask Update Message Fields

Field Name	JSON	Value	Description
messageType	m	"e"	Ask Update message
timestamp	t	Numeric	Milliseconds since midnight ET (BZX, EDGX), or Milliseconds since midnight London (BXE, CXE, DXE)
symbol	s	Alpha	Symbol
askPrice	ap	Price	Ask price; 0 if no asks
askSize	as	Numeric	Ask size; 0 if no asks