FDA Compliance

FDA 510(k) Software Documentation: What You Actually Need to Submit

A practical breakdown of every document the FDA expects for a software-based 510(k) — and the common mistakes that get submissions kicked back.

12 min read · May 2026 · Tolga Ciftci, PreQMS
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If you're preparing a 510(k) submission for a software-based medical device, the documentation requirements can feel overwhelming. This guide cuts through the noise and tells you exactly what you need, in plain language.

Who this is for

Software engineers, regulatory affairs professionals, and startup founders preparing their first 510(k) submission for a Class II software-based medical device. Assumes basic familiarity with FDA processes.

What is a 510(k) and when do you need one?

A 510(k) is an FDA premarket submission that demonstrates your device is substantially equivalent to a legally marketed predicate device. You need one for most Class II medical devices before you can sell them in the US.

For software-based devices, the FDA increasingly scrutinises the software documentation package. A weak software submission is one of the most common reasons for an "Additional Information" (AI) letter — which can delay your clearance by 3–6 months.

The FDA's framework for software

The FDA evaluates software in 510(k) submissions against two primary references:

Common mistake: Treating the software documentation as an afterthought. FDA reviewers are increasingly technical — a shallow SRS or a traceability matrix with gaps will generate an AI letter. Budget time for this.

The core document set

For a typical Class II software device, you need these documents in your Design History File:

1. Software Requirements Specification (SRS)

The SRS defines what your software does — every functional and non-functional requirement. This is the foundation everything else traces back to.

What FDA reviewers look for:

The IEC 62304 standard classifies software into safety classes A, B, and C. Class C (failure could cause death or serious injury) requires the most rigorous documentation — full traceability from requirements to architecture to code to tests.

2. Software Design Specification (SDS)

How your software implements the requirements. Architecture diagrams, module decomposition, data flow. This is your "design output" document in the DHF language.

3. System/Software Test Cases (SSTC)

The test cases that verify each requirement. Each test case must link back to one or more SRS requirements — this is the heart of your traceability matrix.

Common structure:

4. System/Software Test Protocol (SSTP)

The formal document that records test execution — who ran the tests, when, on which version of the software, and the actual results. This is your "testing was done" evidence for FDA reviewers.

5. Traceability Matrix

A table (or document) showing that every SRS requirement has at least one test case, and every test case links back to an SRS requirement. No orphaned requirements, no untested requirements.

FDA's View on Traceability

FDA guidance explicitly states: "The traceability analysis should provide reasonable assurance that all identified risks have been adequately addressed through design." An incomplete matrix is a red flag.

6. Anomaly List (Bug List)

A record of all known software defects, their severity classification, and their resolution. FDA expects you to know your bugs — don't hide them. Classify each by severity and document your rationale for shipping with any open defects.

7. Software Version History

Version control log with release notes for each version. Shows the FDA your development process was controlled.

The traceability requirement in detail

Traceability is the thread that ties everything together. The FDA expects a complete chain:

LevelDocumentLinks to
User NeedsUser Needs document↓ SRS requirements
RequirementsSRS↓ Design outputs, test cases
DesignSDS↓ Code modules, test cases
VerificationSSTC↑ SRS requirements
ValidationSSTP↑ SSTC test cases

Every gap in this chain is a potential AI letter. FDA reviewers will look for requirements with no test cases and test cases with no requirements.

Safety class and documentation depth

IEC 62304 software safety classes determine how deep your documentation needs to go:

ClassDefinitionDocumentation requirement
Class ANo injury or damage to health possibleBasic — SRS, test records
Class BNon-serious injury possibleFull — SRS, SDS, SSTC, SSTP, traceability
Class CDeath or serious injury possibleFull + additional rigor on hazard analysis, FMEA, formal design reviews

Most software-based Class II devices fall into Class B or C. If your software controls treatment delivery, sensor data interpretation with clinical impact, or safety-critical alarms — you're Class C.

Common reasons 510(k) software submissions fail

  1. Untraceable requirements — SRS requirements with no test cases, or test cases that don't reference requirements
  2. Non-testable requirements — "The system shall be user-friendly" with no measurable criteria
  3. Missing anomaly list — FDA expects to see known bugs, not a claim of zero defects
  4. Stale documents — SRS written for version 1.0, tested on version 2.3, without a change control record connecting them
  5. No formal review records — IEC 62304 requires documented design reviews. Email threads don't count.
  6. Cybersecurity gaps — any network-connected device needs a Cybersecurity Bill of Materials (CBOM) and threat model since 2023

How long does it take to prepare the documentation?

For a typical Class B software device at an experienced startup: 8–16 weeks for a first-time submission with a good regulatory consultant. The longest part is usually writing the SRS — not because it's hard, but because it forces engineering decisions that weren't previously captured in writing.

With purpose-built tooling (like PreQMS), the structural and formatting work drops significantly. The intellectual work of defining good requirements doesn't — that's on your team.

"The FDA doesn't want perfect documentation. They want documentation that demonstrates controlled development and traceable decisions. There's a difference." — Common advice from experienced regulatory consultants

Build your 510(k) documentation in PreQMS

SRS, SSTC, SSTP, and traceability matrix — structured, linked, and export-ready for submission.

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