Skip to main content

Whitepaper

Spatial Cadastre L3

A Topology-Enforced Land Ownership Protocol

Document status: This whitepaper is a high-level rationale document and is not the canonical implementation specification. The current normative protocol behavior is defined in docs/yellowpaper.md. Economic, tax, ETH-denominated, NFT, and advanced lifecycle sections in this document include historical or exploratory material and may not reflect the current Sui Move implementation.

⸻

  1. Introduction

Land ownership systems rely on spatial integrity: parcels must not overlap, must belong to a jurisdiction, and must maintain consistent boundaries with neighboring plots.

Traditional cadastral systems enforce these constraints through centralized databases and administrative procedures. This introduces inefficiencies, lack of transparency, and difficulties in synchronizing spatial and legal data.

Spatial Cadastre L3 proposes a blockchain protocol where geometric correctness of land ownership is enforced directly at the execution layer. Transactions that violate spatial rules are rejected by the protocol itself.

In this system, invalid land geometries cannot be recorded on-chain.

The protocol introduces a spatial validation engine integrated into the blockchain runtime, enabling deterministic enforcement of topological rules for cadastral polygons.

⸻

  1. Problem

Existing land registries suffer from several structural issues:

2.1 Spatial inconsistency

Traditional databases allow: • overlapping parcels • gaps between parcels • invalid topologies

These inconsistencies require manual correction.

⸻

2.2 Centralized authority

Cadastral validation is typically performed by a centralized authority, creating: • slow updates • opaque decision-making • corruption risks

⸻

2.3 Lack of deterministic validation

Most GIS systems rely on floating-point arithmetic and procedural validation pipelines, which makes deterministic distributed verification difficult.

⸻

Spatial Cadastre L3 solves these problems by embedding deterministic spatial validation directly into blockchain execution.

⸻

  1. Protocol Overview

Spatial Cadastre L3 is a specialized L3 blockchain network designed for spatial ownership systems.

The protocol enforces topological constraints on cadastral polygons directly during transaction execution.

Key guarantees include: • polygons may share boundaries but may not overlap in area • a polygon may exist in unclaimed space, but if higher-level jurisdictions exist at its location, it must be strictly contained within exactly one parent per level (5.2) • all polygons must have positive area • invalid spatial configurations cannot be recorded

The current implementation separates a deterministic spatial cadastre from a layered market system. Parcel ownership is tracked inside the shared cadastre index via parcel records with explicit owner fields, while economic behavior is layered on top by market contracts.

That market layer now includes a production cascading tax mechanism in Market V2. Upstream tax is created on all payment-bearing flows (register, buy_full, expand_unclaimed, acquire_slice), pooled into an on-chain tax_fund, and later distributed through cascading parent collection (each level keeps a share and forwards the remainder up the hierarchy), owner withdrawal, and permissionless expiry sweep. The market also supports area mutations: expand unclaimed, acquire slice (cross-owner), rebalance slice (same-owner), and merge owned. The detailed semantics for that system are normative in docs/yellowpaper.md.

The canonical production implementation targets Sui Move and SUI-denominated execution rather than an ETH-native settlement model.

The current implementation details are intentionally specified outside this whitepaper:

  • docs/yellowpaper.md — canonical protocol specification
  • docs/architecture.md — implementation architecture and capability model
  • docs/api.md — public API and event surface
  • docs/archive/whitepaper-historical.md — archived historical and exploratory designs

⸻

  1. Current Documentation Map

This whitepaper remains a high-level motivation and framing document only.

  • Use the Yellow Paper for normative behavior.
  • Use the Architecture and API docs for implementation truth.
  • Use the archive doc for ETH/Harberger/NFT-era research and unsupported lifecycle ideas.

⸻

  1. Current Protocol Summary

At a high level, the current protocol is a Sui-based on-chain cadastre with the following characteristics:

  • exact fixed-point integer geometry
  • strict positive-area non-overlap enforcement
  • shared-index storage with parcel owner fields
  • capability-gated lifecycle operations
  • optional market layer on top of the spatial core
  • cascading, bucketed upstream tax in Market V2 with anti-retro guard, delete-after-collect, and sweep semantics

For all detailed semantics, refer to the canonical docs listed above.

⸻

  1. Current Lifecycle Snapshot

The current implementation supports:

  • registration
  • removal
  • ownership transfer
  • forced buyout through the market layer
  • area mutations: reshape, repartition, split, merge (all area-conserving)
  • market operations: expand unclaimed, acquire slice, rebalance slice, merge owned
  • deferred tax accrual on register, buy_full, expand_unclaimed, and acquire_slice
  • batched parent collection through collect_batch
  • owner withdrawal of self_claimable tax via withdraw_tax
  • permissionless expiry cleanup via sweep_expired

Registration validates multipart parcel topology, minimum edge length, compactness, and non-overlap before inserting the parcel into the shared index.

In the market layer, geometry-changing operations also interact with tax versioning. Repartition, expansion, merge, and removal flows either close polygon tax versions or sweep pending child-side tax state so deferred tax accounting remains aligned with current geometry.

⸻

  1. Historical Material

Historical and exploratory material previously embedded in this document has been moved to:

docs/archive/whitepaper-historical.md

That archive preserves earlier ETH/Harberger/NFT-based protocol directions and advertising-market research. The current Sui Move implementation supports full area mutations (reshape, repartition, split, merge), market operations (expand, acquire slice, rebalance, merge owned), and a deferred market-tax lifecycle; normative details live in the Yellow Paper rather than in this historical archive.

⸻

  1. Conclusion

Spatial Cadastre L3 frames the core idea behind the protocol: geometry can be treated as a first-class blockchain invariant.

The current production implementation of that idea is documented in the canonical merca.earth protocol docs rather than in this high-level whitepaper. In particular, the live Market V2 stack now includes a cascading tax architecture with versioned tax buckets, delete-after-collect semantics, anti-retro epoch guards, owner-withdrawable claimable balances, and permissionless expiry sweeps, all specified normatively in the Yellow Paper.

Last updated on