Building an Automated SEC Securities Lending Reporting System from Scratch
The Challenge
A financial institution needed to comply with new SEC (Securities and Exchange Commission) securities lending reporting requirements mandated by FINRA (Financial Industry Regulatory Authority). The institution was already processing Securities Financing Transactions Regulation (SFTR) reports but faced several critical challenges:
- No existing system for SEC-specific reporting workflows
- Complex regulatory requirements with multiple report types (New, Modification, Termination, Cancellation, Correction, Pre-Existing, Delete)
- Tight compliance deadlines requiring reports to be submitted within T+1 (next business day by 01:00 AM)
- Need to process both current and historical transactions differently based on FINRA start dates
- Complex business logic requiring 20+ different reporting scenarios based on transaction lifecycle and state changes
- Integration with existing SFTR processing without disrupting current operations
- File generation and automated transmission to FINRA via SFTP in JSON format with BZip2 compression
- High data volumes requiring efficient batch processing (5,000-10,000 transactions daily)
The institution had existing SFTR reporting infrastructure but needed a completely new parallel system for SEC reporting that could leverage shared data while maintaining independence.
Our Approach
We designed and implemented a comprehensive SEC reporting automation system integrated with the existing SFTR infrastructure. The solution was built incrementally over several months with a focus on reliability, compliance, and maintainability.
Phase 1: Database Architecture & Data Model
- Designed normalized database schema with dedicated SEC tables (SECTradeData, SECEventProcess, SECEventReport)
- Created relationship links to existing SFTR enrichment data to avoid duplication
- Implemented temporal tracking for transaction lifecycle states
- Built stored procedures using table-valued parameters for efficient batch processing
- Established proper indexing strategy for high-volume query performance
Phase 2: Core Processing Engine
- Developed C# object model mapping to database schema using Dapper ORM
- Implemented event-driven architecture for processing securities lending transactions
- Created comprehensive reporting logic engine handling 20+ distinct scenarios (new loans, pre-existing modifications, terminations, counterparty changes)
- Built MD5 hash comparison for detecting actual data changes vs. redundant updates
- Integrated collateral and margin processing logic
Phase 3: Intelligent Report Type Determination
- Developed sophisticated decision engine mapping SFTR action types to FINRA report types
- Implemented business rule overrides based on transaction characteristics (pre/post-FINRA start date, counterparty changes, termination logic)
- Created validation framework ensuring report accuracy before submission
Phase 4: JSON File Generation & Transmission
- Built comprehensive data mapping service transforming database records to FINRA JSON format
- Implemented multiple report type models (SECNewEvent, SECPreExistingEvent, SECTerminationEvent, etc.)
- Created file generation service with proper FINRA naming conventions
- Integrated BZip2 compression for file size optimization
- Developed SFTP transmission service with error handling and retry logic
Phase 5: Batch Processing & Scheduling
- Designed processing schedule aligned with trading hours: 13:30 PM and 16:30 PM batches, plus 23:00 PM final sweep
- Built status tracking through multiple states (Pending Queue, File Sent, Acknowledged, Rejected)
- Created comprehensive logging and monitoring for compliance auditing
Phase 6: Testing & Quality Assurance
- Developed extensive unit test suite using xUnit framework (881 automated tests)
- Created integration tests validating end-to-end workflows
- Built test data factories for reproducible scenarios
- Implemented parallel test execution for rapid feedback
- Established CI/CD pipeline with automated testing in Azure DevOps
The Results
Successful Regulatory Compliance
- 100% on-time submission rate meeting T+1 regulatory deadlines
- Zero compliance violations since go-live
- Complete audit trail for regulatory scrutiny
- Automated generation of all required report types
Operational Efficiency
- Reduced manual processing from ~40 hours/week to zero
- Eliminated human error in report generation and data mapping
- Automated file transmission replaced manual SFTP uploads
- Real-time status tracking provides visibility into processing pipeline
Business Value
- Avoided regulatory penalties (potential millions in fines)
- Eliminated need for additional manual processing headcount
- Reduced operational risk through automation
- Positioned institution for future regulatory changes with flexible architecture
Technologies Used
This case study demonstrates the complexity of implementing regulatory compliance systems in financial services, requiring not just technical expertise but deep understanding of financial regulatory requirements, domain knowledge, integration patterns, performance engineering, and testing rigor.