Regulation Identifier Number (RIN)

A RIN follows a strict 4-part structure: NNNN-XXXX. The first four digits represent the agency code (e.g., 0910 for the FDA, 2060 for the EPA). The final four digits are a unique sequential identifier assigned by the agency to a specific rulemaking docket. This standardized format enables reliable computational parsing and cross-database matching, functioning as a canonical identifier for regulatory text.

A single RIN persists across all stages of a rulemaking action:

• Proposed Rule (NPRM): The initial publication seeking public comment.
• Final Rule: The binding regulation published after the comment period.
• Corrections and Amendments: Technical fixes or substantive updates to the final rule. This persistence allows automated systems to link disparate Federal Register entries into a unified regulatory history chain, preventing citation to superseded or incomplete versions of a rule.

RINs are the primary index key for the Unified Agenda of Federal Regulatory and Deregulatory Actions, published twice yearly. This publication uses the RIN to report the current regulatory status (e.g., 'Proposed Rule Stage', 'Final Rule Stage', 'Completed') and projected timelines for each action. For regulatory intelligence platforms, the RIN is the essential join key between the aspirational timeline in the Agenda and the actual text in the Federal Register.

The first four digits of a RIN are a controlled prefix assigned by the Regulatory Information Service Center (RISC). This prefix maps directly to a specific federal department or independent agency. For example:

• 0938: Centers for Medicare & Medicaid Services (CMS)
• 1545: Internal Revenue Service (IRS)
• 2127: National Highway Traffic Safety Administration (NHTSA) This hierarchical prefix allows for efficient filtering and jurisdictional routing of regulatory monitoring alerts.

The RIN functions as a foreign key linking a regulation to its mandatory economic analysis. Under Executive Order 12866, significant regulatory actions must be accompanied by a Regulatory Impact Analysis (RIA). The RIA is published with the same RIN, enabling automated systems to computationally link the legal text of a rule with its quantified cost-benefit projections and Paperwork Reduction Act burden estimates.

A RIN is distinct from a docket number (e.g., FDA-2023-N-0010). While a docket number identifies the repository for all public comments and supporting materials for a rulemaking, the RIN identifies the regulatory action itself. A single docket may contain materials related to multiple RINs, but a RIN maps to one specific regulatory change. Computational systems must treat the RIN as the primary entity for tracking the rule's legal text, not the administrative docket.

A legislative enactment that has been replaced or rendered obsolete by a newer statute. In the context of RIN tracking, a superseded statute invalidates all associated regulatory actions. Automated amendment tracking must flag any RIN whose underlying statutory authority has been repealed, preventing citation to outdated administrative law.

• Triggers the need for new rulemaking actions with fresh RINs
• Requires continuous monitoring of legislative updates
• Critical for maintaining Good Law Standing in regulatory databases

The automated monitoring and surfacing of updates in statutes and administrative codes. A RIN serves as the primary key for tracking a specific rulemaking action through the Federal Register lifecycle. Change detection systems subscribe to RIN feeds to alert compliance officers when a proposed rule advances to a final rule or is withdrawn.

• Uses RIN as a persistent identifier across NPRM, Final Rule, and Correction stages
• Enables delta computation between proposed and final regulatory text
• Powers real-time compliance dashboards for regulated industries

The automated identification of situations where a statute or legal doctrine has been explicitly annulled or repealed by a subsequent legislative act. When applied to regulatory intelligence, abrogation detection must cascade to all RINs promulgated under the voided authority, marking them as historically superseded rather than currently binding.

• Distinguishes between judicial invalidation and legislative repeal
• Prevents reliance on regulations lacking current statutory basis
• Integrates with Citation Graph traversal to map downstream effects

The computational process of converting diverse legal citation formats into a single canonical form. RINs themselves follow a strict format (e.g., 1210-AB12), but agency references to them in preambles and regulatory text often contain variants. Normalization ensures reliable cross-database matching of regulatory references.

• Handles inconsistent spacing, hyphenation, and agency prefix abbreviations
• Enables Fuzzy Citation Matching for OCR-scanned Federal Register entries
• Foundational step for building a unified regulatory citation index

A binary or graded validation status confirming that a legal authority has not been overruled, superseded, or rendered unconstitutional. For regulations, Good Law Standing is determined by verifying that the RIN's final rule remains in effect, has not been stayed by a court, and is still supported by valid statutory authority.

• Requires real-time integration with court dockets and Congressional actions
• Often displayed as a green/yellow/red status indicator in regulatory research platforms
• Directly analogous to KeyCite and Shepardizing signals for case law