FDA Finalizes Guidance on Computer Software Assurance: What Changed From the Draft

On September 24, 2025, the FDA released its long-awaited final guidance on Computer Software Assurance (CSA) for Production and Quality System Software, replacing the 2022 draft version. This document represents a significant step forward in clarifying how manufacturers should approach software used in manufacturing and quality processes.

Below, we break down what changed from the draft and what medical device companies should know as they update their quality and validation practices.

Why This Guidance Matters

Software plays an increasingly central role in device manufacturing and quality systems think manufacturing execution systems, learning management systems, CAPA tools, SaaS platforms, eQMS, and cloud storage. FDA requires this software to be validated for its intended use, but traditional software validation approaches have often been burdensome, prescriptive, and mismatched to the actual risk.

This guidance reframes validation as “computer software assurance” a risk-based approach designed to reduce unnecessary documentation, promote innovation, and focus effort where it matters most: patient safety and product quality.

Key Changes From the 2022 Draft

1. Alignment With the New QMSR

Since the draft was released, FDA finalized the Quality Management System Regulation (QMSR) in 2024, which will replace most of Part 820 with ISO 13485:2016 requirements (effective February 2026).

• The final CSA guidance explicitly ties assurance practices to this transition.

• Manufacturers should expect FDA to update CSA again in 2026 to fully align with ISO 13485 references.

  
  

2. Superseding Old Validation Guidance

The draft described CSA as a supplement to FDA’s 2002 General Principles of Software Validation. The final version goes further, formally superseding Section 6 of that guidance (Validation of Automated Process Equipment and Quality System Software).

• This means CSA is now the controlling reference for production and quality system software validation.

  
  

3. More Granular Risk Framework

The final guidance strengthens the “intended use + risk” model:

• High process risk = failure could create a quality problem that compromises safety → more rigorous assurance.

• Not high process risk = failure won’t foreseeably compromise safety → proportionally less rigor required.

• Explicit examples now illustrate how the same ERP or MES function may be low- or high-risk depending on context.

  
  

4. Expanded Examples & Testing Methods

The final guidance includes detailed case studies (nonconformance management systems, LMS, PLM, MES, electronic signatures).

• FDA explicitly endorses unscripted testing methods (exploratory, error-guessing, scenario testing) alongside scripted protocols.

• Manufacturers are encouraged to leverage digital records (system logs, audit trails) instead of relying on screenshots or duplicative paper documentation.

  
  

5. Vendor Assurance & Cybersecurity Expectations

Compared to the draft, the final guidance sets clearer expectations around vendor and third-party software:

• Review supplier practices (SDLC, certifications, cybersecurity posture, SOC/ISO reports).

• Consider vendor-provided testing, audit trails, encryption, and SBOMs as part of your assurance strategy.

• Leverage purchasing controls and supplier evaluation to scale your validation effort appropriately.

  
  

6. Regulatory Reporting Clarity for PMA/HDE Devices

The final guidance clarifies how changes to production or quality system software interact with 30-day notices and annual reports for PMA/HDE devices.

• If a software change may compromise safety → 30-day notice.

• If it does not compromise safety → annual report.

  
  

What This Means For You

• Update SOPs: Ensure your software validation or assurance SOPs reference CSA rather than legacy FDA validation guidance.

• Emphasize Risk-Based Decision-Making: Document intended use and process risk for each software feature or function.

• Streamline Documentation: Shift from “test everything, capture everything” toward evidence commensurate with risk.

• Review Vendor Controls: Build vendor evaluation and cybersecurity checks into your supplier management processes.

• Plan for QMSR Alignment: Anticipate adjustments in 2026 as ISO 13485 formally replaces most of Part 820.

  
  

Please Be More Specific These Guidance Documents Make My Eyes Bleed

• Update SOPs:

  • Ensure your software validation or assurance SOPs reference CSA rather than legacy FDA validation guidance.

  • Define an intended use assessment as the first step.

  • Incorporate the FDA's risk framework (high process risk versus not high process risk)

  • Add testing strategy flexibility for unscripted testing.

  • Emphasize the use of digital evidence  (audit trails, logs, system-generated reports) instead of screenshots or duplicative paper.

  • For software used in production or QMS, integrate CSA risk analysis into change control.

  • Document how changes are evaluated for impact on intended use and risk.

  • Explicitly tie CSA records to change requests.

  • For PMA/HDE devices:

    • Clarify when a software change → 30-day notice (if it may compromise safety).

    • Clarify when a software change → annual report (if it does not compromise safety).

  • Add vendor evaluation requirements for software developers and SaaS/cloud providers:

    • Review of SDLC practices.

    • Certifications (ISO, SOC).

    • Cybersecurity posture (SBOMs, encryption, audit trails, access controls).

  • Define acceptable reliance on vendor validation and documentation as part of the assurance package.

  • Document a risk-based approach to vendor oversight (not all vendors need full audits).

• Emphasize Risk-Based Decision-Making: Document intended use and process risk for each software feature or function.

• Streamline Documentation: Shift from “test everything, capture everything” toward evidence commensurate with risk.

• Review Vendor Controls: Build vendor evaluation and cybersecurity checks into your supplier management processes.

• Plan for QMSR Alignment: Anticipate adjustments in 2026 as ISO 13485 formally replaces most of Part 820.

  
  

Bottom Line

The final CSA guidance reflects FDA’s push toward modern, agile, and least-burdensome quality practices. For medical device manufacturers, this is an opportunity to simplify software validation, reduce overhead, and align with international standards without compromising patient safety.

Polaris Biomedical can help you assess how this guidance impacts your quality system and build a tailored roadmap for compliance.