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NewOrderMultileg (MsgType AB)

applicationFIX 4.4FIX 5.0 SP2

NewOrderMultileg is the FIX message with MsgType AB, defined in FIX 4.4 and FIX 5.0 SP2. It is an application-level message: it carries a business event rather than managing the session. Its body has 73 top-level members once the standard header and trailer are counted.

A real NewOrderMultileg

NewOrderMultileg · FIX 4.4
TagFieldWire valueMeaning
8BeginStringFIX.4.4
9BodyLength130
35MsgTypeABNew Order - Multileg
49SenderCompIDBOARTEAM
56TargetCompIDCOUNTERPARTY
34MsgSeqNum2
52SendingTime20240101-12:00:00.000
11ClOrdIDORD-10042
54Side1Buy
555NoLegs1 entry1repeating group
600LegSymbolEXAMPLE
60TransactTime20240101-12:00:00.000
40OrdType1Market
10CheckSum030
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.

Message body — FIX 4.4

Components are listed by name and link to their own page rather than being expanded inline; repeating groups are expanded, including where they nest.

Message body — FIX 5.0 SP2

Components are listed by name and link to their own page rather than being expanded inline; repeating groups are expanded, including where they nest.

What changed between the dialects

Present in FIX 5.0 SP2 only (14)

tag 1089, tag 1090, DisplayInstruction, tag 1133, tag 1069, tag 1377, tag 1378, tag 1092, TriggeringInstruction, tag 1080, tag 1081, tag 1091, StrategyParametersGrp, tag 1190

Handle NewOrderMultileg 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);​if (message.msgType === "AB") {  message.name;            // "NewOrderMultileg"  // fields are keyed by tag; repeating groups live on message.groups}​// Problems come back as data, never as exceptions:issues;                    // FixIssue[]fix.validate(message);     // dictionary-level problems

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 decoderSource on GitHub