Predicate Device Selection for 510(k) Submissions

1. Key takeaways

Three categories of devices can serve as predicate devices (Predicates) for a 510(k). First, devices that were legally in commercial distribution in the United States before May 28, 1976 (preamendments devices). Second, devices that have been reclassified from Class III to Class II or Class I under FD&C Act §513. Third, devices that have been found substantially equivalent through the 510(k) process. In addition, devices authorized through a De Novo request under FD&C Act §513(f)(2) may also serve as predicates for subsequent submissions.

• May 28, 1976 is the statutory watershed date for the US device framework; preamendments devices are a primary predicate source.
• Reclassified Class III devices and previously cleared 510(k) devices are the other two legitimate predicate categories.
• De Novo-authorized devices can also serve as predicates under FD&C Act §513(f)(2).
• Intended use equivalence takes priority over technical similarity when screening candidate predicates.
• Multiple predicates are permissible, provided the submission explains the evidentiary coverage of each and the chain of evidence closes.
• Devices marketed abroad but never legally marketed in the United States cannot serve as predicates.
• Predicate eligibility and pathway choice should be confirmed before dossier preparation begins, not after review questions arrive.

2. Legal basis

The table below summarizes the authorities that define which devices may lawfully serve as predicates and how the comparison must be documented. Entries were verified against the electronic Code of Federal Regulations and FDA database resources in 2026.

3. Expert insights

Insight 1: May 28, 1976 is the watershed date of United States device law, and it must be written correctly every single time. That day is the effective date of the medical device amendments to the FD&C Act. Devices already in commercial distribution before that date may continue to be sold until classification is completed, and they constitute the origin of a large share of the predicate pool relied upon by 510(k) sponsors. Devices introduced after that date must first pass through a premarket pathway before they can enter the market. Because the date anchors the entire predicate framework, any error in citing it undermines the credibility of the comparison section.

Insight 2: Predicate selection prioritizes intended use equivalence; technical similarity comes second. The substantial equivalence determination compares intended use first and technological characteristics afterward. A device that is technically similar but indicated for a different condition will be flagged in the first round of review, and the sponsor will be asked to substitute a more appropriate predicate. When GRZAN screens candidate predicates, the first operation performed is a word-by-word comparison of the intended use statements, not a comparison of technical parameters. Only candidates whose intended use statements align are then assessed on technology.

Insight 3: Multiple predicates may be cited, but the evidentiary coverage of each must be explained. When a single predicate cannot cover all of the features of the subject device, citing more than one predicate is acceptable. However, the submission must state, predicate by predicate, which portion of the evidence each one supports, and the overall chain of evidence must close without gaps. Unclear allocation of evidentiary coverage across multiple predicates is a common deficiency cited during review, so the mapping should be explicit and traceable within the dossier itself.

Insight 4: Devices marketed overseas but never marketed in the United States cannot serve as predicates. This follows from the same principle behind the fact that FDA does not recognize regulatory approvals granted by other authorities. Marketing history in China, the European Union, or Japan does not confer predicate eligibility in the United States. Sponsors arriving with a strong foreign portfolio must still anchor their 510(k) to a US-lawful predicate or select a different pathway.

In practice, predicate screening is best treated as a documented, auditable exercise rather than an informal judgment. The screening record should show which candidates were considered, why each was kept or eliminated, and the exact text of the intended use statements that were compared. This record becomes the backbone of the comparison section of the dossier and provides reviewers with a transparent trail from candidate pool to final predicate choice. It also protects the project schedule: when the rationale is already written, responding to early review questions about predicate legitimacy becomes a matter of pointing to the existing file rather than reconstructing the analysis under deadline pressure.

4. Practical recommendations

• Search the FDA 510(k) database by product code, list the candidate predicates, and record the K number of each candidate.
• Compare the intended use statement word by word for every candidate and eliminate those whose indications are inconsistent.
• State explicitly in the dossier which of the legitimate predicate categories the selected device belongs to.
• Where multiple predicates are used, draw an evidence coverage map that shows which section of the submission each predicate supports.
• If no suitable predicate exists, move immediately to a De Novo pathway assessment instead of forcing a weak submission through review.

5. Verification checklist

• □ Candidate predicates retrieved in the FDA 510(k) database and K numbers recorded.
• □ Word-by-word comparison of intended use completed.
• □ Confirmed that the predicate belongs to one of the three legitimate source categories.
• □ Clearance date and K number of the predicate recorded.
• □ Where multiple predicates are used, evidence coverage map completed.
• □ Confirmed that the predicate is still legally marketed in the United States (not withdrawn).

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, US Agent and local testing support for the United States market. Our team manages FDA establishment registration and listing, 510(k)/De Novo/PMA submissions, and supports post-market reporting obligations. Business enquiries: info@grzanglobal.com