BRIEF: Bounded-Context Regeneration of Long Documents with Verifiable Structural Topology

Long legal and financial documents combine extreme length with checkable dependencies, including numbered clauses, section containment, defined-term reuse, and internal cross-references. We study whether such documents can be regenerated without relying on a single generation prompt whose context grows with document length. We present BRIEF (Bounded Regeneration In Exact Form), a graph-conditioned schedule for bounded-context regeneration. BRIEF extracts a reference graph, builds a target graph, and writes each clause from a short structural brief containing its number path, required terms, and cross-references. The generator never receives source prose or sibling clauses. Across the controlled length sweep, BRIEF maintains cross-reference fidelity near 0.98 while keeping maximum input-prompt length approximately constant at 86 tokens. On CUAD contracts and EDGAR EX-10 exhibits, BRIEF improves extractor-verifiable section and cross-reference topology over one-pass generation. A retrieval-based linkage audit shows lower source linkability after regeneration, although substantial residual leakage remains. A separate coherence analysis shows that preserving this topology does not by itself preserve reference semantics. A bounded, dependency-ordered plug-in, BRIEF-L, restores most of this within-release coherence, from near zero to between 0.44 and 0.70 of cited clauses, while keeping cross-reference fidelity within 0.03 of BRIEF and adding about 0.08 to EDGAR linkage. A cross-generator replication on Llama-3.1-8B preserves the bounded-context advantage and the low-coherence finding, while showing that BRIEF's relative advantage over the naive bounded baseline is generator-dependent. BRIEF does not establish formal anonymity, general semantic equivalence, or preservation of legal and financial meaning.