Version 1.0 — Apache 2.0

The Open Standard for
Modern Lead Exchange

LEX is a modern, extensible EDI specification for exchanging sales leads across manufacturers, dealers, systems, and platforms — in any industry, any format, without vendor lock-in.

Get Started Read the Spec

5

Message Types
4

EDI Formats
9+

Industries
15

Lead Status Values
4

Language Libraries
Apache 2.0

License

Overview

A Standard Built to Last

Today’s lead exchange integrations are bespoke, fragile, and expensive to maintain. Where shared standards exist, they have been captured by dominant platform vendors — through proprietary variants, integration brokerage fees, and controlled governance. LEX is designed from the ground up with open governance, explicit anti-capture protections, and a simplicity budget that keeps the standard implementable.

LEX encodes the complete lead lifecycle — from a customer's first browsing session through order placement, delivery, and deal closure — in a single, consistent message format that works across every industry vertical.

No membership fees — implement LEX freely without payment or approval

No mandatory certification body — conformance levels are self-declared against public test vectors

Anti-capture governance — modeled on HTTP/2 RFC and OpenJS Charter protections

Simplicity budget — core structure understandable in two documents, optional blocks additive

LEX Message Structure

// Every LEX message follows this envelope
{
  "lex": {
    "version": "1.0.0",

    "header": {
      // messageId, messageType, timestamp
      // senderId, receiverId, correlationId
    },

    "payload": {
      // Content varies by messageType:
      // LEAD | ASSET | ACKNOWLEDGMENT
      // SUBSCRIPTION | LEAD_CLOSURE
    }
  }
}

Core Features

Everything a Lead Exchange Needs

Designed for the full lifecycle — from first browse to closed deal — across any format and any industry.

Open Governance

Apache 2.0 licensed with anti-capture protections. No dues, no approvals, no vendor gatekeepers. Any entity can implement and contribute.

Four EDI Formats

JSON-EDI (recommended), XML-EDI, X12, and EDIFACT. All formats carry the same data model — choose the format your stack already speaks.

Full Lead Lifecycle

15 lead status values covering SHOPPING through ORDER, DELIVERED, and ARCHIVED — with bidirectional flow and non-linear progression support.

Any Industry

Ground transport, aviation, maritime, heavy equipment, real estate, technology, and general B2B procurement. One standard, every asset class.

Cross-Platform Libraries

Compiled from a single Haxe source: JavaScript/Node.js, Python 3, Java, and C# .NET libraries with identical APIs and consistent validation.

Compliance Built-In

GDPR, UK GDPR, CCPA, India DPDPA, China PIPL, Brazil LGPD, South Africa POPIA, Japan APPI, Singapore PDPA, Canada PIPEDA, South Korea PIPA-K, Saudi Arabia PDPL, Thailand PDPA, Switzerland nFADP, and US state privacy laws — geographic compliance built in. Consent records, data governance blocks, and deduplication fingerprints are core — not afterthoughts.

Message Formats

Same Data Model. Four Formats.

LEX is format-agnostic. Pick the wire format your infrastructure already supports — all four are first-class.

json-edi-lead.json Recommended

{
  "lex": {
    "version": "1.0.0",
    "header": {
      "messageId": "550e8400-e29b-41d4-a716-446655440000",
      "messageType": "LEAD",
      "timestamp": "2026-03-28T14:30:00Z",
      "senderId": "DEALER-001",
      "receiverId": "MANUFACTURER-ABC"
    },
    "payload": {
      "lead": {
        "leadId": "LEAD-2026-001234",
        "status": "EXPRESSED_INTEREST",
        "customer": {
          "firstName": "Jane",
          "lastName": "Smith",
          "email": "jane.smith@example.com",
          "phone": "+13125559876"
        }
      }
    }
  }
}

xml-edi-lead.xml

<?xml version="1.0" encoding="UTF-8"?>
<lex version="1.0.0">
  <header>
    <messageId>550e8400-e29b-41d4-a716-446655440000</messageId>
    <messageType>LEAD</messageType>
    <timestamp>2026-03-28T14:30:00Z</timestamp>
    <senderId>DEALER-001</senderId>
    <receiverId>MANUFACTURER-ABC</receiverId>
  </header>
  <payload>
    <lead>
      <leadId>LEAD-2026-001234</leadId>
      <status>EXPRESSED_INTEREST</status>
    </lead>
  </payload>
</lex>

x12-lead.txt

ISA*00*          *00*          *ZZ*DEALER-001     *ZZ*MANUFACTURER-A *260328*1430*^*00501*000001234*0*T*:~
GS*LX*DEALER001*MFRABC*20260328*1430*1*X*005010~
ST*850*0001~
BEG*00*SA*LEAD-2026-001234**20260328~
N1*BY*Jane Smith*92*CUST-001~
N3*123 Main Street~
N4*Springfield*IL*62701*US~
PER*IC**EM*jane.smith@example.com*TE*+13125559876~
PO1*1*1*EA***IN*EXPRESSED_INTEREST~
CTT*1~
SE*8*0001~
GE*1*1~
IEA*1*000001234~

edifact-lead.txt

UNB+UNOC:3+DEALER-001:14+MANUFACTURER-ABC:14+260328:1430+000001234'
UNH+1+ORDERS:D:96A:UN'
BGM+220+LEAD-2026-001234+9'
DTM+137:20260328:102'
NAD+BY+CUST-001::92++Jane Smith'
CTA+IC+:jane.smith@example.com'
COM++TE:+13125559876'
LIN+1++EXPRESSED_INTEREST:SA'
UNT+8+1'
UNZ+1+000001234'

Lead Lifecycle

15 Status Values. Complete Coverage.

LEX tracks the full journey from initial discovery through closed deal. Status transitions are bidirectional — supporting real-world non-linear customer journeys.

CART

Shopping cart / wishlist

SHOPPING

Customer browsing / research

EXPLORING

Active interest, comparing options

TRADE_IN

Trade-in asset evaluation

EXPRESSED_INTEREST

Formal interest declaration

RESERVATION

Provisional booking / hold

APPOINTMENT_REQUEST

Scheduling showroom visit

IN_NEGOTIATION

Active deal discussion

ORDER

Final purchase commitment

DELIVERED

Asset handed to customer

ABANDONED

Customer disengaged

ARCHIVED

Historical / completed lead

Conformance

Three Tiers. Self-Declared.

No mandatory certification body, no fees. Conformance levels are validated against public test vectors.

Basic

Minimum for production

✓ Valid message envelope
✓ Required field compliance
✓ MessageID uniqueness
✓ ACKNOWLEDGMENT responses
✓ Timestamp validity (±60s)

Standard

Required for DMS integration

✓ All Level 1 requirements
✓ Full lifecycle support (15 statuses)
✓ Business rule validation
✓ Lead Closure support
✓ Bidirectional flow

Full

OEM & platform certification

✓ All Level 2 requirements
✓ Consent record compliance
✓ Deduplication fingerprints
✓ Multi-format support
✓ Subscription management

View Full Conformance Spec

Ready to Implement?

Start with the Getting Started guide or dive straight into the full specification. Reference libraries for JavaScript, Python, Java, and C# are ready to use.

Get Started → Read the Specification

The Open Standard for Modern Lead Exchange