A copywriter drafts three positioning lines with an AI assistant, picks the one that works, and an account manager cleans it up before it goes in a deck. Three months later a rival pitches the same client with a suspiciously similar line. Or the client's own marketing hire, hired after the campaign launched, tells their boss the tagline was actually her idea from a brainstorm six months earlier. Either way, the agency needs to show what it produced and when, and a Slack thread with a screenshot of an AI chat window is not going to do that.
The ownership question doesn't get simpler once AI is part of the process
Agencies have always faced authorship disputes: a former employee who claims a campaign was their concept, a client who reuses a deliverable after the contract ends and denies where it came from, a competitor pitch that lands suspiciously close to work still in review. AI-assisted production adds a second layer on top of the old one. Now there's also the question of how the work was made, whether a human wrote the strategy deck or a model drafted the first pass and a strategist edited it, and whether that distinction changes who can claim it.
Under the EU AI Act, Article 50 puts a labelling duty on AI-generated and AI-assisted content in certain circumstances. An agency that ignores this exposes itself on two fronts at once: it can't show who authored the deliverable, and it can't show how it was produced. Neither gap is solved by a good contract clause alone, because a clause describes what should have happened. It doesn't record what actually did.
What happens when someone disputes it
Three scenarios come up often enough to plan for.
A client stops paying an invoice and claims the strategy was theirs to begin with, so the agency's fee doesn't apply. A departing employee takes a portfolio piece to a new employer and presents it as solo work. A competing agency pitches a concept close enough to one still under NDA that somebody has to explain, credibly, who had it first.
In each of these cases, the underlying work already exists somewhere: drafts, files, an email thread. What's missing is a record that doesn't depend on the agency's own word. An internal file's creation date can be changed. A sent email proves a date but not necessarily the content that mattered, especially if drafts kept moving after it was sent. What a dispute actually needs is a version of the deliverable, tied to a fixed point in time, that the agency did not produce itself after the fact and that the other side can check independently.
Copyright already exists, the problem is proving it
Under the Berne Convention, copyright in an original work arises automatically at the moment of creation, with no registration required, and that protection is recognised across the convention's member countries. This applies to agency deliverables the same as anything else: a copy deck, a brand identity, a strategy document, a piece of code. Nobody needs to file anything for copyright to exist.
The part that doesn't happen automatically is evidence. If a client or a competitor disputes when a piece of work existed or who made it, the agency has to produce something dated and specific enough to answer the question, and it has to be something the other side can check without simply trusting the agency's own files. That's a separate problem from whether copyright exists, and it's the one that actually decides who wins a dispute.
The added complication of AI-assisted work
Work made with AI assistance raises a second question alongside authorship: what was the human contribution, and is it documented as such. A strategist who used an AI tool to draft ten headline variants and then picked, rewrote, and combined two of them made a real creative decision, but nothing about that decision is visible in the final file unless it was recorded somewhere at the time.
This matters for two separate reasons. First, under Article 50 of the AI Act, agencies operating in or serving the EU market have a labelling obligation for AI-generated content in defined circumstances, and a dated declaration of how a piece was produced is the kind of record that answers a regulator's question later without anyone having to reconstruct it from memory. Second, in an ownership dispute, being able to show the declaration your team made about a deliverable at the time it was produced, human authored, AI assisted, or AI generated, is stronger than reconstructing the claim after the fact when memory and incentives have both changed.
What a dated record adds before handoff
This is where sealing a deliverable before it leaves the building earns its place in an agency's process. The file gets a cryptographic hash, a fixed value derived from its exact bytes that changes if anything in the file changes. That hash, along with a declaration of how the work was produced, gets a qualified electronic timestamp from a Qualified Trust Service Provider. Under eIDAS, a qualified electronic timestamp carries a legal presumption as to the date and time it indicates and the integrity of the data bound to it. That presumption is what shifts a dispute from "trust our word" to "check the record yourself."
The certificate produced alongside the seal resolves to a public verification page, so a client, a court, or an opposing lawyer can check the file and the declaration against the record without needing an account or contacting the agency at all. That's the part that actually matters in a dispute. A record only the agency can produce is a record the other side can question. A record either party can independently verify is much harder to argue with.
Client sign-off benefits from the same layer for a different reason. A deliverable that needs a client's approval before launch, a final creative concept, a legal disclaimer, a signed-off strategy document, can carry a qualified electronic signature with the same standing as a handwritten one under ZertES in Switzerland and Swiss Code of Obligations Article 14 paragraph 2bis for the underlying handwritten-form equivalence. That closes off a second, more common dispute: the client who approved a concept verbally or in a chat message and later claims they never signed off on the direction the agency ran with.
Building this into agency delivery
The habit worth adopting is small: seal the deliverable at the point it goes to internal review or out to the client, not months later when a dispute has already started. Attach the declaration honestly at that moment, human authored, AI assisted, or AI generated, rather than deciding after the fact what looks better. And treat client sign-off the same way, with a qualified signature on the final approved version rather than an email thread that has to be pieced back together later.
None of this replaces a contract that spells out ownership terms clearly. What it does is give the agency something to point to when a contract clause alone isn't enough, because the other side is disputing the facts the clause depends on: who made the work, when, and how. A dated, independently verifiable record answers that without asking anyone to take the agency's word for it.
To see how this fits an agency's delivery workflow specifically, our agencies page covers client sign-off and proof of creation in more detail. For the mechanics of sealing a file, how it works walks through the process end to end.
