NoNested2PartyIDs (FIX tag 756)

NumInGroupFIX 4.4group counter

NoNested2PartyIDs (tag 756) is a NumInGroup field defined in FIX 4.4. It appears in 8 message types, always optionally. Its datatype is NumInGroup, which makes it a repeating-group counter: its value is the number of entries that follow, not a quantity in its own right.

At a glance

Tag: 756
Name: NoNested2PartyIDs
Datatype: NumInGroup (int)
Dialects: FIX 4.4
Messages: 8

What the specification says

Number of Nested2PartyID (757), Nested2PartyIDSource (758), and Nested2PartyRole (759) entries

Descriptions are quoted from the FIX Orchestra sources under the Apache 2.0 licence.

A real message using tag 756

TradeCaptureReport · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	211
35	MsgType	AE	Trade Capture Report
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
571	TradeReportID	EXAMPLE
570	PreviouslyReported	N	not reported to counterparty
32	LastQty	1000000
31	LastPx	1.09210
75	TradeDate	20240101
60	TransactTime	20240101-12:00:00.000
552	NoSides1 entry	1	repeating group
54	Side	1	Buy
37	OrderID	ORD-10042
78	NoAllocs1 entry	1	repeating group
79	AllocAccount	EXAMPLE
756	NoNested2PartyIDs2 entries	2	repeating group
757	Nested2PartyID	EXAMPLE
757	Nested2PartyID	EXAMPLE
10	CheckSum	043

Edit and decode it yourself

Shown with | separators for readability. On the wire FIX uses SOH (0x01), an invisible control byte — and because BodyLength and CheckSum are computed over the actual bytes, the two forms have different checksums. Both are valid and both decode here.

Open in the full decoder →

Generated from the FIX 4.4 dictionary and verified at build time: it parses and validates with no issues. Open the decoder to try your own message.

Where tag 756 appears

Requiredness is a property of the message, not of the field: the same tag can be optional in one message and conditionally required in another.

Message	MsgType	Requiredness	Where in the message
AllocationInstruction	J	Optional	inside OrdAllocGrp › NestedParties2
AllocationReport	AS	Optional	inside OrdAllocGrp › NestedParties2
Confirmation	AK	Optional	inside OrdAllocGrp › NestedParties2
ConfirmationRequest	BH	Optional	inside OrdAllocGrp › NestedParties2
MultilegOrderCancelReplace	AC	Optional	inside LegOrdGrp › LegPreAllocGrp › NestedParties2
NewOrderMultileg	AB	Optional	inside LegOrdGrp › LegPreAllocGrp › NestedParties2
TradeCaptureReport	AE	Optional	inside TrdCapRptSideGrp › TrdAllocGrp › NestedParties2
TradeCaptureReportAck	AR	Optional	inside TrdAllocGrp › NestedParties2

Wire format

The number of entries in the repeating group that follows. The next field on the wire is the group's delimiter tag. @boarteam/fix parses the value as a number and reports parse/invalid-int when it does not lex as one; the raw string is kept either way.

Read tag 756 in TypeScript

decode.tsts

import { createFixEngine } from "@boarteam/fix";import { dictionary } from "@boarteam/fix-dict-fix44";const fix = createFixEngine(dictionary);const { message, issues } = fix.parse(raw);// NoNested2PartyIDs is a group counter, so the entries live on message.groups —// NOT on message.fields. message.fields[756] is undefined.const entries = message.groups[756] ?? [];for (const entry of entries) {  // entry.fields is keyed by tag; entry.groups holds nested groups}

Decode this in your own code

The same engine that produced the decoded example above is an Apache-2.0 npm package with zero runtime dependencies. It runs in Node and in the browser, and parse() returns problems as data instead of throwing.

npm i @boarteam/fix @boarteam/fix-dict-fix44

Try the decoder Source on GitHub