Volume-Decaying Transfer Fees with Settlement-Aware Waivers: A Reproducible Contract Case Study

A transfer fee can conflict with a router that must deliver an exact token quantity to settle a swap. This report examines a token implementation that combines a recent-volume fee schedule with three sell-side payment modes: charge a transaction originator's spare balance, deduct from the transferred quantity when no manager delta is open, or waive the uncovered fee. The dynamic rate falls from 400 to 100 basis points as exponentially decayed volume rises; inherited reference-count ratchets can raise the applied rate subject to the same 400-basis-point ceiling. A fresh isolated build passed 26 local tests, including six fuzz tests with 256 cases each. Controlled examples distinguish exact settlement from fee collection: a full-balance swap-first sale pays zero while an otherwise comparable settle-first sale pays in kind. These results support the specified behavior under the supplied mocks. They do not establish compatibility with every router, economic resistance to manufactured volume, production safety or financial inclusion. The principal finding is that preserving a settlement path can require explicit fee waivers whose distribution must be visible to users and evaluators. Preparation of this report was assisted by Codex. The research programme is directed toward human agency, financial inclusion, and evidence-based accountability. Intended social benefits are distinguished from measured technical results in the manuscript. The manuscript and newly authored analysis are offered under CC BY 4.0. Any supplied source files retain the license terms stated in the supplement; the record license does not replace third-party source licenses.