The UFC fights under the Unified Rules of MMA, and that rulebook bans a specific list of moves: eye pokes, groin strikes, fence grabs, strikes to the back of the head and spine, and several others. When a fighter breaks one of them, the referee has exactly three tools — a warning, a point deduction, or disqualification — and which one gets used depends on whether the foul was accidental, how much damage it did, and whether it's happened before.

The full list of what's illegal

Beyond the fouls covered in detail below, the Unified Rules also ban headbutting, biting, hair pulling, fish-hooking (hooking fingers into an opponent's mouth, nose, or ears), small-joint manipulation (grabbing and twisting a single finger or toe), strikes to the throat or a grab of the trachea, and kicking or kneeing the head of a downed opponent. Holding an opponent's shorts or gloves for control, and using the fence to strike an opponent, are also fouls. Timidity — intentionally avoiding contact or faking an injury to get a break — can be penalized too, though referees rarely reach for it.

Eye pokes

An eye poke happens when a fighter's fingers make contact with an opponent's eye, usually during an open-hand strike or a grip attempt. The rule itself is specific: extending the fingers toward an opponent's face is a foul on its own, before any contact happens, because it's the posture that causes pokes.

When a poke lands and a fighter can't see, the referee calls time and the ringside doctor examines the eye. If the poke looks accidental — which is the ruling in most cases — the fighter typically gets a warning rather than a point deduction, and the fight resumes once the doctor clears them or after a reasonable recovery pause. If the fighter genuinely cannot continue and enough of the fight hasn't happened yet to let the scorecards decide it, the bout ends in a no contest. A high-profile heavyweight title fight in October 2025 ended exactly that way, after a double eye poke left the champion unable to see for the rest of the round — and the aftermath pushed athletic commissions to openly debate making eye-poke point deductions automatic instead of a judgment call. That debate hadn't produced a settled rule change as of this writing, so expect the current warn-first approach to keep drawing criticism until it does.

Groin strikes

Any strike, grab, pinch, or twist to the groin is illegal, intentional or not. This is the one foul with a guaranteed recovery window written into the rules: a fighter who's been hit low gets up to five minutes to recover, as long as the ringside doctor believes they can still continue. If the fighter says they're ready sooner, the referee restarts the fight as soon as practical. If the five minutes runs out and the fighter still can't go, the bout ends — either as a no contest (if too little of the fight has happened) or a technical decision sent to the scorecards (if enough rounds are in the books). That five-minute allowance is specific to low blows; other fouls don't come with the same guaranteed clock.

Fence grabs

The cage's fence isn't a handhold. Grabbing it to stop a takedown, to pull yourself back to your feet, or to gain any positional advantage is a foul. It's also one of the most common — fighters do it reflexively when they're being taken down — which is why referees usually warn first and only deduct a point if it keeps happening or clearly changes the outcome of an exchange.

Strikes to the back of the head and spine

The back of the head — the area roughly from the crown down the base of the skull — and the spine are both off-limits as strike targets, because the risk of serious injury is much higher there than anywhere else on the body. This foul shows up most often in the clinch or on the ground, where a fighter throwing legal punches can drift into an illegal zone without much room to correct. Referees judge these on intent and effect: a glancing shot that clearly wasn't aimed there usually draws a warning, while a fighter who keeps landing behind the ear after being told to stop is a candidate for a point deduction.

Grounded fighters, 12-6 elbows, and the rule that keeps changing

This is the part of the rulebook that's actually moved recently, and it's worth understanding because it doesn't apply the same way at every event. In mid-2024, the sport's rules body voted to legalize the straight-down "12-to-6" elbow — a strike thrown like a hammer, top to bottom — that had been banned since the Unified Rules were first written. At the same time, it redefined what makes a fighter "grounded" and therefore protected from knee and kick strikes to the head: under the old rule, any part of a hand touching the mat counted; under the new rule, it takes a body part other than a hand or foot — a knee, hip, or forearm — touching the canvas.

Both changes officially took effect in November 2024. The catch is that every state athletic commission has to individually adopt the Unified Rules, and not all of them have. Some commissions kept the old rules on the books well into 2025, which meant a UFC event overseen by one of those commissions still banned 12-6 elbows and used the old, hands-count-as-grounded definition — while a card in a different state ran under the new version. That split is why you can't assume the same rulebook applies to every fight you watch; it depends on which commission is regulating that specific event.

What refs actually do, in order

For almost any foul, the referee's default move is a verbal warning, which has zero effect on the scorecards. A point deduction is the next step up, usually one point, based on how bad the foul was and what it cost the other fighter — except for one case the rules make automatic: an intentional foul that injures an opponent badly enough to affect the fight, but not badly enough to end it, carries a mandatory two-point deduction, no discretion involved. Disqualification is reserved for fouls severe enough to end the fight outright, or for a fighter who keeps committing them after being warned and docked. For how a deducted point actually changes a scorecard, see how UFC scoring works; for what happens when a foul ends a fight early, see every way a UFC fight can end.

The practical read for anyone watching the next card: most fouls you'll see are accidental and drawn from the same short list — fingers near the eyes, a knee that strays low, a hand that finds the fence — and they cost the offending fighter nothing beyond a stern word from the referee. The ones worth watching closely are the repeat ones, because that's when a warning turns into a point, and a point can be the difference between winning and losing a decision.