A De Novo review is FDA's risk-based classification route for a novel device that has no legally marketed predicate, but whose risks can be controlled by general controls, or by general and special controls. A granted request classifies the device into class I or class II, creates a new classification regulation for that device type, and allows the device to serve as a predicate for future 510(k) submissions (FDA: De Novo Classification Request).
For software and AI-enabled devices, De Novo is often the realistic route: the technology is new, no predicate fits, and a PMA would be disproportionate to the risk. This article covers where the pathway comes from, when it applies, what the request must contain under 21 CFR 860.220, how FDA accepts and reviews it, and what a grant means for later products.
Background and legal basis
Without a predicate, a new device is automatically class III. De Novo is the mechanism that lets FDA classify it by risk instead.
The pathway was created by section 207 of the Food and Drug Administration Modernization Act of 1997 (FDAMA), which added section 513(f)(2) to the FD&C Act. Under FDAMA, a device first had to receive a not substantially equivalent (NSE) decision through a 510(k) before a De Novo request could be filed. Section 607 of the Food and Drug Administration Safety and Innovation Act of 2012 (FDASIA) added a second option: a direct De Novo request, without a prior 510(k).
FDA codified the procedure in 21 CFR Part 860, Subpart D through a final rule published on 5 October 2021 and effective on 3 January 2022. Subpart D has seven sections:
| Section | Title |
|---|---|
| 860.200 | Purpose and applicability |
| 860.210 | De Novo request format |
| 860.220 | De Novo request content |
| 860.230 | Accepting a De Novo request |
| 860.240 | Procedures for review of a De Novo request |
| 860.250 | Withdrawal of a De Novo request |
| 860.260 | Granting or declining a De Novo request |
When the pathway applies
Under 21 CFR 860.200(b), a De Novo request can be submitted for a single device type in one of two situations:
after an NSE determination in response to a 510(k); or
when the requester determines there is no legally marketed device on which to base a substantial equivalence determination.
The second route is the one most SaMD companies use. It depends entirely on the quality of the predicate search, because FDA may decline a request if the device is of a type already approved through a PMA, or already classified into class I, II or III (21 CFR 860.260(c)(5) and (6)).
FDA recommends a Pre-Submission before filing, to get feedback from the review division on the regulatory approach (FDA: De Novo Classification Request). For a novel software function, that is the cheapest point at which to test the intended use, the device description and the predicate search. Our article on AI/ML FDA submission strategy and classification covers how to frame that question for AI-enabled devices.
What the request must contain
21 CFR 860.220(a) lists the required content. Any omitted item must be justified in a separate section (860.220(c)), and the requester must update a pending request with new safety and effectiveness information as it becomes available (860.220(d)).
| Item | Content | Section |
|---|---|---|
| Table of contents | Volume and page for each item | 860.220(a)(1) |
| Administrative information | Requester, U.S. representative if applicable, establishment registration number if applicable | 860.220(a)(2) |
| Regulatory history | Prior 510(k)s, PMAs, HDEs, IDEs, 513(g) requests, Pre-Submissions or earlier De Novo requests, or a statement that there were none | 860.220(a)(3) |
| Device name | Generic and proprietary or trade name | 860.220(a)(4) |
| Indications for use | Condition, patient population and all labelled uses, including prescription or over-the-counter | 860.220(a)(5) |
| Device description | The device, components, relevant properties and principles of operation | 860.220(a)(6) |
| Alternative practices | Existing alternatives for the same condition | 860.220(a)(7) |
| Classification summary | The searches used, a list of potentially similar classification regulations, PMAs, HDEs, 510(k)s, EUAs and product codes, and a rationale for why the device differs | 860.220(a)(8) |
| Risks and mitigations | Probable risks to health and the proposed mitigations, including special controls if class II is proposed | 860.220(a)(9) |
| Proposed special controls | An initial draft for a class II recommendation, and how they provide reasonable assurance of safety and effectiveness | 860.220(a)(10) |
| Classification recommendation | Class I or II, and why the controls are adequate | 860.220(a)(11) |
| Standards | Relevant voluntary consensus standards and how the device meets them | 860.220(a)(12) |
| Summary of studies | Summaries of nonclinical and clinical studies | 860.220(a)(13) |
| Benefit and risk | Why the evidence is valid scientific evidence and the probable benefit outweighs the probable risk | 860.220(a)(14) |
| Technical sections | Nonclinical data, software information including device hazard analysis, and clinical data | 860.220(a)(15) |
| Other information, samples, labelling | Bibliography, other relevant data, samples on request, labels and labelling | 860.220(a)(16)–(19) |
Three sections carry most of the weight. The classification summary (a)(8) is where the predicate search is either convincing or not. The risks and mitigations (a)(9) and proposed special controls (a)(10) become the basis for the classification regulation that later devices of the same type will follow. For software, 860.220(a)(15)(ii) requires all relevant software information and testing, including an appropriate device hazard analysis. Our article on SaMD technical documentation covers how to structure that evidence.
Submission, acceptance and review
Since 1 October 2025, De Novo requests must be submitted as electronic submissions using eSTAR, unless exempted, through the CDRH Portal (FDA eSTAR guidance for De Novo requests). De Novo requests are subject to a user fee, and FDA only starts technical screening once the fee has been paid.
Acceptance. Under 21 CFR 860.230, FDA notifies the requester within 15 days whether the request is accepted. FDA may refuse to accept a request if, for example, the requester has an open premarket submission for the device, the request is incomplete or incorrectly formatted, or it covers more than one device type (860.230(c)(1)). FDA states that the acceptance review is largely automated within eSTAR. If the eSTAR is incomplete, the request is placed on hold, and if a replacement is not received within 180 days, it is treated as withdrawn.
Substantive review. FDA reviews whether a device of the same type already exists and whether the proposed controls are adequate. Deficiencies may be resolved through interactive review. If not, FDA issues an Additional Information letter and the request goes on hold. The requester has 180 calendar days to respond in full, and FDA states that no extensions will be granted. Without a complete response, the request is considered withdrawn (21 CFR 860.250(a)(1)).
Timelines. Under 21 CFR 860.240(a), FDA will review the request and issue an order granting or declining it within 120 days of receipt or acceptance. FDA's De Novo page also states a performance goal of 150 review days for a decision, where review days exclude time on hold for an Additional Information request. FDA may inspect relevant facilities before deciding (860.240(c)).
Grant, decline and withdrawal
| Outcome | What happens | Source |
|---|---|---|
| Grant | Device authorised for marketing; new classification regulation for the device type; device can serve as a predicate for future 510(k)s; Federal Register notice of the classification order, including any special controls, within 30 days | 21 CFR 860.260(a); FDA De Novo page |
| Decline | Written order listing each ground; the device remains class III and cannot be legally marketed | 21 CFR 860.260(b)–(d) |
| Withdrawal | No complete response within 180 days, inspection refused, or written notice by the requester | 21 CFR 860.250 |
FDA also publishes a granting order and a decision summary. The decision summary is published voluntarily, and FDA describes it as a resource for manufacturers that may later use the device as a predicate.
The grounds for declining are listed in 860.260(c). Besides insufficient controls or evidence, they include a device type already approved through a PMA or already classified, false statements or material omissions, labelling that does not comply with parts 801 or 809, and, under 860.260(c)(11), significant unsolicited changes to the indications for use or technological characteristics after acceptance. After a decline, FDA states that the requester should generally either submit a PMA or collect additional information and submit a new De Novo request.
A hypothetical SaMD filing
Hypothetical example: a Dutch SaMD company has developed a software function that does not match any existing device type. It holds a Pre-Submission to agree the predicate search approach, then documents its searches of classification regulations, 510(k)s, De Novo grants and product codes as the classification summary under 860.220(a)(8).
It files a direct De Novo request through eSTAR, recommending class II. Its proposed special controls cover software verification and validation, performance testing, cybersecurity and labelling, and each risk in the 860.220(a)(9) summary points to the test or labelling section that mitigates it. The software section includes the device hazard analysis required by 860.220(a)(15)(ii).
FDA issues an Additional Information letter during substantive review. The company responds within the 180 days, without changing the indications for use or the technological characteristics, which avoids the decline ground in 860.260(c)(11).
What a grant means for later products
A grant is more than a marketing authorisation for one device. It creates the classification regulation, and for class II the special controls, that apply to every later device of that type, including the requester's own next versions. Competitors can use the granted device as a predicate for their 510(k)s, and the decision summary shows them what evidence FDA relied on.
That has two practical consequences. First, special controls should be drafted with the product roadmap in mind, because they will apply to later versions. Second, the normal post-market obligations start at grant, including establishment registration and device listing. Our article on FDA device listing covers the FURLS steps, and our regulatory strategy for the EU and US covers how a De Novo plan fits alongside CE marking.
Conclusion
De Novo is the route when no predicate exists and the risks can be controlled without a PMA. The request is a classification proposal: the classification summary, risks and mitigations and proposed special controls carry as much weight as the test data. With eSTAR mandatory since 1 October 2025, a 15-day acceptance check and a 180-day limit on Additional Information responses with no extensions, the file has to be complete before it is submitted.
If you are planning a De Novo request for a novel software device, our US FDA consulting team can help, or contact MedQAIR.
Frequently asked questions
Is a De Novo grant the same as 510(k) clearance?
No. A 510(k) clearance is based on substantial equivalence to a legally marketed predicate. A De Novo grant classifies a new device type into class I or II where no predicate exists, and creates a new classification regulation (21 CFR 860.260(a)).
Can I submit a De Novo request without filing a 510(k) first?
Yes. Since FDASIA in 2012, a requester who determines that no legally marketed predicate exists can submit a De Novo request directly (21 CFR 860.200(b)(2)).
Can a De Novo device be used as a predicate?
Yes. FDA states that a device classified into class I or II through a De Novo request may be used as a predicate for future 510(k) submissions, where applicable.
What happens if FDA declines my De Novo request?
The device remains in class III and cannot be legally marketed. FDA issues a written order listing the grounds under 21 CFR 860.260(c). The requester should generally either submit a PMA or address the deficiencies and submit a new De Novo request.
Is eSTAR mandatory for De Novo requests?
Yes, for requests submitted from 1 October 2025, unless an exemption applies under FDA's guidance on the electronic submission template for De Novo requests.
How long does a De Novo review take?
Under 21 CFR 860.240(a), FDA will issue a grant or decline order within 120 days of receipt or acceptance. FDA's stated performance goal is a decision within 150 review days, which exclude days on hold for an Additional Information request. The requester has 180 calendar days, with no extension, to respond to such a request.
