Category 3 can fly over people, and it cannot fly over an open-air assembly. Section 107.130(a) sets eligibility at an injury no greater than the equivalent of 25 foot-pounds of kinetic energy from a rigid object, with no exposed rotating parts that would lacerate skin and no safety defects. Section 107.125 then limits where that aircraft may actually go: not over an open-air assembly, and over any person only inside one of two operating conditions.
The rule
The aircraft side mirrors Category 2 with a higher energy number. The applicant submits a declaration of compliance under §107.160. The aircraft must be eligible under §107.130(a), listed on an FAA-accepted declaration as eligible for Category 3, and labeled under §107.130(b)(1). The label is English, legible, prominent, and permanently affixed. The applicant supplies remote pilot operating instructions and keeps a product-support process. If the label is later damaged or missing, §107.135 lets the remote pilot relabel in English for the duration of the operation before flight over people. Eleven foot-pounds remains the Category 2 number. Category 3 does not become Category 2 by flying more carefully.
The operating side is §107.125(b) and (c). The remote pilot must not operate the aircraft over open-air assemblies of human beings. Over any human being, one of two conditions has to be true. The operation is within or over a closed or restricted-access site, and all human beings on that site are on notice that a small unmanned aircraft may fly over them. Or the aircraft does not maintain sustained flight over any human being unless that person is directly participating in the operation, or is located under a covered structure or inside a stationary vehicle that can provide reasonable protection from a falling aircraft. Those sheltered and participating people are the same people §107.39(a) and (b) already name. Everyone else, outside a closed site, gets only the non-sustained path.
How to apply it
Treat the site first. A fenced, badge-access industrial plant, with every employee briefed that a drone may fly overhead during the shift, is the §107.125(c)(1) case. Sustained flight directly over those notified workers is permitted. Remote ID from a FRIA is not what makes that plant flight legal. The closed site and the notice are the condition.
A public park is not that site. Category 3 may still pass over people who are not participating when the aircraft does not maintain sustained flight over them. One brief pass above two joggers, without hovering, circling, or returning over them, is a non-sustained pass. The pilot does not need a §107.39 waiver for that non-sustained pass, and a signed release is not the rule. Category 3 is not limited to closed-access sites only. The second branch exists for the brief transit.
A parade, a festival, and a packed outdoor crowd are open-air assemblies. Section 107.125(b) bars Category 3 from operating over them. Announcing the flight on loudspeakers so "the whole crowd is on notice" uses the closed-site sentence on the wrong place. Remote ID, which can support sustained flight over an assembly for Categories 1, 2, and 4, does not authorize Category 3 to do that operation. The open-air assembly page is where those three categories and the sustained-flight examples live. The overview of all four categories is on operations over people.
A plant, a park, and a parade
Monday is the plant. The Category 3 aircraft is listed and labeled. The gate is badged. The shift briefing told every person on the property that the aircraft may fly over them. You hold over the equipment row for the inspection. That hover is sustained flight, and §107.125(c)(1) allows it.
Tuesday is the park mapping line. Two joggers cross the path. You are already in a point-to-point line, you pass once, and you do not circle back. They are not crew, and they are not under a roof or inside a parked car. The pass is still the non-sustained alternative in §107.125(c)(2).
Wednesday the producer wants the parade. The aircraft broadcasts Remote ID. The announcer tells the crowd. The street is open. That flight over the parade is prohibited. A parade is an open-air assembly, and Category 3 operations over open-air assemblies are never permitted, regardless of notice or Remote ID.
The trap
One trap says sustained flight over people is prohibited for every category, so the plant hover is illegal. Category 3 specifically permits sustained flight over people inside the closed or restricted-access site when everyone has been notified. Another trap says the plant works only if the aircraft broadcasts Remote ID from a FRIA. That is not the §107.125(c)(1) condition.
The park item flips the other way. It says Category 3 may only ever operate over people inside closed-access sites, or that any overflight of a non-participant needs a §107.39 waiver. A brief pass that does not hover, circle, or return is permitted over non-participants. The parade item offers Remote ID, or an altitude above 200 feet, as if either one amended §107.125(b). They do not. The on-notice option applies to Category 3 flights at closed or restricted-access sites, not to open-air assemblies.
The Category 2 injury number is the nearby distractor when a question only asks for foot-pounds. Use 25 for this category. Drill the plant, the joggers, and the parade on the free practice test. The course teaches the closed-site path and the non-sustained path as the only two ways over a person.