How to Find a Predicate Device for Your 510(k) Submission

The predicate device is the legal and scientific foundation of every 510(k) submission. FDA must determine that your device is substantially equivalent to a device already legally marketed — and that determination starts with which predicate you choose.

Choose the wrong predicate and you'll spend months answering FDA questions. Choose the right one and clearance becomes a matter of documentation, not debate.

What makes a predicate valid?

FDA's substantial equivalence standard has two prongs. Your device must have:

1. The same intended use as the predicate — meaning it treats, diagnoses, cures, or monitors the same condition or patient population
2. The same or different technological characteristics — if different, those differences must not raise new questions of safety or effectiveness

Both prongs must be satisfied. A device with the same technology but a different intended use is not substantially equivalent. Neither is a device with the same intended use but technology that introduces new risks FDA hasn't evaluated.

Step 1 — Start with product code, not device name

Most people start their predicate search by typing a device name into FDA's database. This is the wrong approach. Device names are inconsistent and FDA-assigned names often don't match how manufacturers describe their products.

Start with the product code — the three-letter FDA code that maps to a device type under a specific 21 CFR regulation. Every cleared 510(k) has one. If you know your device category, find the product code first using FDA's product code database, then search for predicates within that code.

Product codes enforce that you're comparing apples to apples. A cardiac monitor predicate for a glucose monitor is legally invalid no matter how similar the technology looks.

Step 2 — Filter for recent clearances

An older predicate isn't necessarily weaker — but FDA reviewers pay attention to how recently a predicate was cleared. A predicate from 2018 is generally preferable to one from 2003, all else equal, because it reflects more recent FDA thinking on the device type.

More importantly: predicates that are themselves based on older predicates create a chain of substantial equivalence. If your predicate was cleared based on a 1998 device, and that device's technology has evolved significantly, FDA may question whether the entire chain holds.

Target predicates cleared within the last 5-7 years when possible. Use the year range filter to narrow your search.

Step 3 — Match intended use precisely

The intended use statement in a 510(k) is a legal claim, not a marketing description. FDA reviewers compare your intended use statement word by word against the predicate's intended use. Scope creep — claiming a broader intended use than your predicate supports — is one of the most common reasons FDA issues an Additional Information request.

Read the predicate's intended use from the 510(k) summary PDF on FDA.gov, not from the manufacturer's website. The cleared language is what matters. Your intended use should track it closely, narrowing only when your device genuinely has a more limited indication.

Step 4 — Evaluate technological characteristics honestly

If your device uses the same technology as the predicate — same materials, same energy source, same design principles — your SE argument is straightforward. Document the similarities and move on.

If your technology differs, you need to answer two questions for each difference:

1. Does the difference raise a new question of safety or effectiveness that FDA hasn't previously evaluated?
2. If yes, can performance data demonstrate that your device is at least as safe and effective as the predicate despite the difference?

Honest answers to these questions early will determine your testing strategy. Don't discover a technological gap during FDA review — build your test plan around it from the start.

Step 5 — Shortlist 3-5 candidates, then narrow

Don't commit to a single predicate immediately. Shortlist 3-5 candidates that pass the initial filter — same product code, recent clearance, matching intended use — then evaluate each against your technological characteristics.

The strongest predicate is the one where:

• Intended use overlap is maximal
• Technological differences are minimal
• The predicate itself was cleared without conditions or special controls you can't meet
• The applicant is a credible market participant (not a shell company or abandoned product)

Run this evaluation in a comparison view before writing a word of your submission.

Common mistakes that delay clearance

• Choosing a predicate based on brand recognition rather than regulatory fit. The biggest company's device isn't necessarily your best predicate.
• Using a predicate that was itself cleared via De Novo. De Novo decisions establish new device types — they're valid predicates, but the review is more intensive.
• Ignoring special controls. If your predicate was cleared with special controls, your device must also comply with those controls or explain why it doesn't need to.
• Assuming a recalled predicate is disqualified. A recall doesn't automatically invalidate a predicate — but it adds complexity that FDA will scrutinize.