Nested2PartyID (FIX tag 757)

StringFIX 4.4

Nested2PartyID (tag 757) is a String field defined in FIX 4.4. It appears in 8 message types, always optionally.

At a glance

Tag: 757
Name: Nested2PartyID
Datatype: String
Dialects: FIX 4.4
Messages: 8

What the specification says

PartyID value within a "second instance" Nested repeating group. Same values as PartyID (448)

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

A real message using tag 757

NewOrderMultileg · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	178
35	MsgType	AB	New Order - Multileg
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
11	ClOrdID	ORD-10042
54	Side	1	Buy
555	NoLegs1 entry	1	repeating group
600	LegSymbol	EXAMPLE
670	NoLegAllocs1 entry	1	repeating group
671	LegAllocAccount	EXAMPLE
756	NoNested2PartyIDs2 entries	2	repeating group
757	Nested2PartyID	EXAMPLE
757	Nested2PartyID	EXAMPLE
60	TransactTime	20240101-12:00:00.000
40	OrdType	1	Market
10	CheckSum	010

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 757 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	Conditional	inside OrdAllocGrp › NestedParties2
AllocationReport	AS	Conditional	inside OrdAllocGrp › NestedParties2
Confirmation	AK	Conditional	inside OrdAllocGrp › NestedParties2
ConfirmationRequest	BH	Conditional	inside OrdAllocGrp › NestedParties2
MultilegOrderCancelReplace	AC	Conditional	inside LegOrdGrp › LegPreAllocGrp › NestedParties2
NewOrderMultileg	AB	Conditional	inside LegOrdGrp › LegPreAllocGrp › NestedParties2
TradeCaptureReport	AE	Conditional	inside TrdCapRptSideGrp › TrdAllocGrp › NestedParties2
TradeCaptureReportAck	AR	Conditional	inside TrdAllocGrp › NestedParties2

Wire format

Free-form text. Any byte except the SOH separator is legal, so values are not trimmed or case-folded on the wire. @boarteam/fix keeps the value as a string; format rules are checked by validate(), which reports validate/invalid-value rather than throwing.

Read tag 757 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);const field = message.fields[757];field?.name;   // "Nested2PartyID"field?.raw;    // the verbatim wire stringfield?.value;  // coerced to a string

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