Postal 4-state family — format provenance and usability notes
====================================================================

This file records the engineering and provenance boundary for the postal
formats implemented by Sythos Barcode Universal: USPS POSTNET, USPS PLANET,
Royal Mail 4-State Customer Code (RM4SCC), KIX, Australia Post 4-State, Japan
Post 4-State and USPS Intelligent Mail Barcode (IMb / OneCode).

Implementation
--------------

The TypeScript implementation and generated JavaScript in this repository are
original Sythos work and are distributed under the MIT License. The shared
height-coded classifier, state profiles, checks, Reed–Solomon arithmetic,
combinatorial IMb mapping and API dispatch are not copied from another barcode
implementation. The npm package has no runtime dependencies.

Public technical descriptions of the postal alphabets, bar heights, framing,
checks and payload envelopes were used as engineering input. The implementation
represents those public format rules in original Sythos data structures. This
file does not reproduce a standards document or grant certification.

Independent validation boundary
-------------------------------

BWIPP and bwip-js were invoked locally as independent black-box oracles. Their
rendered output was compared with Sythos encode/decode results for all seven
formats. They were used exclusively for verification and counter-checking; no
source code, lookup table, generated asset or runtime dependency from those
projects is copied into or shipped by this SDK. Agreement is engineering
evidence, not an endorsement or a licence grant.

Ownership and naming
--------------------

POSTNET, PLANET and IMb/OneCode are associated with the United States Postal
Service. RM4SCC is associated with Royal Mail. KIX is associated with the Dutch
postal system. Australia Post and Japan Post own or administer their respective
postal specifications and marks. Names are used descriptively to identify the
public symbology; this project is not endorsed, certified or operated by any of
those organisations.

Patent, copyright and trademark review
--------------------------------------

The code in this repository is MIT-licensed original Sythos work. Whether a
particular jurisdiction, implementation, service mark, specification edition or
postal-indicia programme imposes additional conditions is a separate legal
question. Users shipping a commercial postal workflow should obtain their own
professional review and any operator approval required for production mail.

[TO VERIFY] Current patent-family status and any jurisdiction-specific claims
for each postal symbology have not been independently searched in this project.

[TO VERIFY] Current trademark, certification-mark and operator-indicia rules
were not independently cleared here. Report a concrete notice, licence term or
conflicting source through a GitHub issue so it can be reviewed and recorded.

This engineering note intentionally keeps those questions visible instead of
making a broad “patent-free” or “certified” claim. See `LICENSE`, `NOTICE.md`
and `licenses/README.md` for the project-wide boundary.