Section 513(g) settles classification, not equivalence

A sponsor unsure what class a device falls into, or whether it needs a 510(k) at all, has two ways to ask FDA directly: a Q-Submission under the pre-submission program this blog has already covered, or a formal request under Section 513(g) of the FD&C Act. The two get treated as interchangeable more often than the statute supports. A 513(g) request is a narrower instrument than a Pre-Sub, built to answer one specific question with a written, fee-bearing, statutorily clocked response — and the question it answers is not the one a sponsor most wants answered once a submission is actually in front of a reviewer.

One question, with a 60-day clock attached

Section 513(g) directs FDA, on receipt of a written request, to provide a written statement of the classification of a device and the requirements applicable to it within 60 days. That statutory clock is what separates a 513(g) request from a Q-Submission, where FDA's own performance goals govern scheduling and nothing in the statute forces an answer by a fixed date. A sponsor that needs a decision on the record, by a date it can plan around, has a reason to use 513(g) that a Pre-Sub meeting request doesn't offer.

What FDA will actually say back

A 513(g) response addresses the agency's assessment of the generic type of device, the device class and product code, and whether a PMA, a 510(k), or neither is required — along with the other basic requirements that attach to that class. It does not evaluate performance data, and it does not tell a sponsor whether its device is substantially equivalent to anything. That determination is made during an actual 510(k) review under Section 513(i), on the specific comparison a chosen predicate supports — a question 513(g) is not built to reach, however completely the request describes the device.

Non-binding, but not disposable

FDA's own guidance on the program describes a 513(g) response as non-binding: it isn't a classification decision and doesn't constitute clearance or approval. In practice, the agency intends to honor what it told a sponsor unless a later submission describes a materially different device or a materially different intended use. That's a narrower promise than a binding ruling, but a wider one than a Pre-Sub's informal feedback, which the agency has never held itself to at all. A sponsor that gets a 513(g) answer and then changes the device's intended use before filing has spent the fee on an answer to a question it no longer has.

The fee is real, and it doesn't come back

Unlike a Pre-Sub, a 513(g) request carries its own user fee, assessed annually under the device user fee schedule, with a reduced rate for a qualifying small business. FDA opens its 60-day review clock only once the request and the fee have both been received, and the fee isn't refunded if the request is withdrawn partway through review. That cost structure is itself a signal about what the tool is for: a sponsor still iterating on what the device even is should be having that conversation in a Pre-Sub, informally, before paying to lock a specific device description into a formal record.

What the request itself has to contain

FDA's current procedural guidance on the program, revised in August 2024 to replace a version dating to December 2015, sets out what a complete request needs: a clear statement of the question being asked, a full description of the device and its intended use, and enough supporting detail — photographs, engineering drawings, a proposed classification with the sponsor's own reasoning attached — for a reviewer to answer without guessing at facts the sponsor left out. A request that describes the device loosely and asks FDA to supply the classification from scratch is asking the agency to do the sponsor's own threshold analysis, which is a request 513(g) doesn't oblige FDA to satisfy inside its 60-day clock.

Where this meets the rest of the file

A submission-strategy worksheet that keeps a 513(g) request's narrow, fee-bearing classification question separate from a Q-Submission's broader, non-binding, no-fee conversation about testing and predicates — and separate again from the substantial-equivalence determination neither one makes — is previewed in the launch catalog. If your team decides between these two differently, the shelf takes that correction directly.