Technical
ML engineering and model validation
Accuracy, robustness and performance. Does the model return correct results, and hold up under unusual or adversarial inputs?
Independent AI-governance audits
Generative AI is optimised for fluency, not truth. We audit whether a system’s outputs mean what your organisation needs them to mean — the layer your accuracy, fairness and compliance checks cannot reach.
Generative AI fails most dangerously not when it is obviously wrong, but when it is convincingly wrong in ways that matter.
That happens when its output collapses a distinction that matters in your field, implies something the evidence does not support, or answers a different situation from the one its user is in. Nothing is fabricated. The words are true. But the meaning is wrong.
Most organisations already assure three layers of AI risk. Each has someone responsible for it, a budget to support it, and a method for assessing it. The fourth — semantic risk — has no coverage today, so meaning failures are found by complaint, by press coverage or in court, after the harm has been done.
ML engineering and model validation
Accuracy, robustness and performance. Does the model return correct results, and hold up under unusual or adversarial inputs?
Responsible-AI and ethics review
Bias and fairness. Are outcomes equitable across groups, and consistent with the values the organisation states?
Legal and compliance
Regulatory conformity. Does the system meet the applicable rules, with the records to demonstrate it?
Linguistics and semantics
Meaning and interpretation. Does the output mean what the organisation needs it to mean: true to the domain, and right for the situation?
The airline’s chatbot told a grieving customer that a bereavement fare could be claimed back after the journey had been taken.
Nothing in the answer was invented: the bereavement fare was real. The policy required the claim to be made before travel, and the chatbot reversed the condition the entitlement turned on.
Source“How can I mislead you? Air Canada found liable for chatbot’s bad advice on bereavement rates”CBC News, 2024
An experimental hiring tool, trained on a decade of the company’s own hiring decisions, learned to prefer the pattern of who had been hired before.
It invented nothing and optimised exactly as designed. “People we hired before” had quietly stood in for “people we should hire again”, and those are not the same idea.
Source“Amazon scraps secret AI recruiting tool that showed bias against women”Reuters, 2018
A dealership’s chatbot was talked into offering a vehicle for one dollar, and into calling the offer binding.
It knew everything about the car. What it misread was the exchange it was in: an adversarial joke, answered in the register of an authorised sale.
Source“A Chevy for $1? Car dealer chatbots show perils of AI for customer service”VentureBeat, 2023
Drawing on Semiosphere’s linguistic and technological expertise, the Semantic Integrity Framework specifies how we look at generative AI outputs, how we identify failures of meaning, how we interpret and classify them, and what harm we report. The white paper provides a summary of the Framework and its application.
Between your document and the output, meaning diverges in describable ways: a polarity reversed (not eligible becomes eligible), an obligation softened (must becomes may), a defined term used loosely, a rule delivered as a promise, a conclusion resting on a premise never stated, an answer that can be read two ways. Twenty-five of them, in six groups.
Every confirmed failure is scored on severity, frequency, governance exposure and stealth — how likely it is to pass unnoticed — so findings can be ranked against one another.
Every audit follows an established, structured sequence of analysis and evaluation, and every recommendation resolves back to an output that occasioned it.
Where failure would do most harm, mapped with your domain experts, and what we expect to find written down before we look.
Designed scenarios, run more than once, so a one-off slip is not mistaken for systematic behaviour.
Every output recorded word for word, with the context needed to reproduce it.
Each output held to the six lenses. A failed lens opens a finding, named with its mechanism and its risk type.
Severity, frequency, governance exposure and stealth. Scores are structured expert judgement, evidenced against the captured output — not measurement.
Fixes prescribed, the same scenarios re-run, residual risk recorded.
If you need to travel immediately or have already travelled and would like to submit your ticket for a reduced bereavement rate, kindly do so within 90 days of the date your ticket was issued by completing our Ticket Refund Application form.
The chatbot’s answer, as reproduced in Moffatt v. Air Canada, 2024 BCCRT 149
The airline’s published bereavement-fare policy, which required the reduced fare to be requested before travel and did not provide for a retrospective claim. In an engagement this is your own document, cited to the clause.
Nothing is invented: the reduced bereavement fare is real. What moved is when it may be claimed, and that is the condition the entitlement turns on. A reader following the answer correctly concludes they may travel first and claim after.
A public case, scored here to show the instrument. No client engagement is described on this page, and the scores are our own illustration rather than a commissioned assessment. Scores are structured judgement against anchored scales, not measurement.
An audit states which scenarios were run, what each output was held against, and what came back. That is a dated, bounded statement about your system — the thing an assurance file needs and a demonstration cannot give.
A finding is reported so that an engineer, a general counsel and a board take the same meaning from it: what went wrong, what it contradicts, what it would cost. The argument stops being about whether the output “feels” wrong.
Every finding carries a remediation written against your system, and the same scenarios are re-run afterwards with the residual risk recorded. An identified-and-fixed finding, with its retest beside it, is the strongest position available to you.
Written for governance, risk, assurance and legal teams. What it covers:
Two engagements, each complete in itself. The Semantic Risk Diagnostic is a quick, fixed-fee screen of one system: it shows where its outputs depart from the documents they are meant to follow, which kinds of failure recur, and whether a closer look is warranted. The Semantic Risk Audit applies the full Framework to one system, with expert analysis of every finding, a scored risk matrix, remediations written for your system, and a retest plan to confirm they hold. Each is scoped and bought on its own, so you commission only what the evidence calls for. Semantic Risk Assurance, which keeps a remediated system under continuous review, is in development.
“Do we have a meaning problem, and where?”
£4,000–£8,000two to three weeks
An automated screen. The platform runs a capped sample of your system’s outputs against the documents they are meant to follow, and ranks what it flags.
Not an audit. No flag is reviewed by the auditor before it reaches you, and a machine screen raises some things expert judgement would discard. Nothing in it is a scored finding.
“How bad, how often, and what do we change?”
£25,000–£50,000four to six weeks, one engagement£15,000–£25,000 (founding-client rate through January 2027)
The complete method applied by hand to one system. Retrospectively, over a transcript export you already hold — no production access, no change control — or live against designed scenarios. The report is the same either way.
“Is it still safe next month?”
Not yet availablean annual subscription, per monitored system
A monitor in your environment, our review of what it flags, and periodic re-testing, so that a system which passed its audit is still passing after the next model update.
It will run after an audit, which supplies the authority set and the scenarios the monitor uses. Tell us if you want it when your audit is scoped.
No commercial relationship with model providers or assurance tooling vendors, no outcome-linked fee, and a conflict check before engagement. The report prescribes; your people implement; the retest runs against your fix.
Transcripts and documents are held under NDA, in the UK, and destroyed at the end of the engagement on a stated timetable. Nothing you supply is used to train anything. Any third-party model that touches your material is named before engagement rather than discovered in a DPIA.
Both consultancy engagements are fixed fee against a scope agreed before work starts. No day rate, and no open-ended commitment. A diagnostic contractually joined to an audit is not a diagnostic, so the two are bought as two orders.
Professional indemnity cover is in place. The method is published in full, so it can be challenged before you buy and continued by someone else if it has to be. We will speak to your board, your auditor or your regulator about it.