This document and the free and open source software referenced sits at the core of the innovative developments in REFLOW technical work-packageand implements a novel signature scheme for the specific use-case of material passports whose integrity, provenance and portability is granted by means of provable cryptography. The format of this document is that of an academic publication (Computer Science –Cryptography and Security, cs.CR) which being submitted to open publishing platforms and made freely available to the scientific community under the Creative Commons License (CC BY-NC-SA 4.0), see:Creative Commons —Attribution-NonCommercial-ShareAlike 4.0 International —CC BY-NC-SA 4.0 The latest version of this document is available on: https://github.com/dyne/reflow-crypto