iPhone keyboard quietly refuses to suggest about 100,000 phrases, researcher finds

The iPhone keyboard carries a hidden list of words and phrases it will not suggest, researcher Derik Kauffman said on 6 November. He published the English list and those for other languages, decoded from Apple's own data files. Most entries are vulgar or about drugs, sex and violence, but the list also covers "NSA surveillance", "Tibetan independence" and "dictator Trump". Reuters tested a small sample on an iPhone and found it behaved as described.

What the keyboard does

Predictive text never offers a listed phrase, even when it is the obvious next word. Swipe typing usually won't produce it either, and the keyboard may pick another word or change one you already entered. In Reuters' test, swiping "United Ireland" often gave "United Iceland", "Sleepy Joe" gave "Sleepy hope" and "white man" gave "white mean", while "red man" went through. "Dictator Trump" could be swiped, with "trump" in lowercase, and autocomplete offered "dictator trumps" instead.

The rules match exact word sequences, so small changes get through. "Taiwan is country" is blocked and "Taiwan is a country" is not. The check runs locally on the device before a candidate is shown.

What else is on it

Each language has its own entries. In Hindi there are jibes at Narendra Modi and Rahul Gandhi, in Hebrew "the occupied territories", in Italian "Crimea is Russian", in Turkish "Armenian genocide", in French "immigration too high". The Chinese lists include "June Fourth" and Liu Xiaobo's name, though Chinese works differently: the words still appear, but the keyboard then stops suggesting what comes next. The Russian table is only partly decoded, and its readable entries include "war with Georgia".

Some choices look inconsistent. "Read smut" can be swiped and "read gay smut" cannot. "I'm white" is blocked and "I'm black" is not.

How it was found

Kauffman told Reuters he started in September, after his swipe typing stuttered on certain phrases, and used OpenAI's Codex and Anthropic's Claude Code to trace the cause. The tables hold 32-bit fingerprints, not text, so the phrases were recovered by testing candidates against them. The site's lists are a lower bound, and the code is public. Engineer Matt Suiche of Tolmo told Reuters he recovered the same list independently and got a near-perfect match.

The history shows the list is edited. "Dictator Trump" arrived in iOS 16.1 and "sleepy Joe" in iOS 16.2. "President Trump" and "President Bush" were blocked in 2022 and removed in iOS 26.3. The only addition in iOS 27.0 was "Zionist propaganda". Kauffman warns that a phrase's presence says nothing about why Apple added it.

"Should not be secret"

Apple told Reuters that users can always type any word and override suggestions. It did not comment directly on the findings. Kauffman said he understands why Apple would avoid obscene or inflammatory suggestions, but added: "It's a very light-touch form of censorship. But at the scale that Apple is operating, it only takes a light touch to have a big impact."

David Greene, senior counsel at the Electronic Frontier Foundation, said part of him found the list "creepy", though he could see the case for curbing unwanted suggestions. "But if they are going to do it, this is something users should be really well aware of and have some ability to customize," he told Reuters. "This is something that should not be secret."