What undercover marketing is
Undercover marketing (also called stealth marketing) is advertising that does not present itself as advertising. A business pays for promotion, but the person receiving the message does not realise it is paid for. It can be a stranger in a bar who happens to rave about a drink, a five-star review that looks like it came from an ordinary customer, or a product that appears in the middle of a movie scene. The technique exists because consumers have learned to tune out conventional advertising. A recommendation that appears unsolicited carries far more weight than a billboard, and businesses have every incentive to manufacture that impression.
That incentive creates a legal problem. In Australia, the Competition and Consumer Act 2010 (Cth) and the Australian Consumer Law (the ACL), which is Schedule 2 of that Act, do not regulate advertising because it is annoying. They regulate conduct that is misleading or deceptive or likely to mislead or deceive. Undercover marketing is engineered around concealment, and concealing the fact that a message is advertising is often precisely what makes it misleading. A campaign that succeeds in fooling its audience has, in many cases, also broken the law.
This article walks through how the three main undercover techniques operate, who is involved, when the ACL bites, what the regulator can do about it and where a lawyer earns their fee.
Who is involved
Undercover marketing is not a single transaction. Several actors play a part, and each can attract liability:
- The business: The advertiser pays for the campaign and carries the primary responsibility for it. The ACL does not allow a business to outsource its compliance to a promoter, an agency or an influencer.
- The promoter: The "ad spy", the conversational "leaner", the influencer or the employee who delivers the disguised message. The ACL applies to "a person", so promoters can be pursued in their own right. The ACCC's enforcement work has targeted brands and the people who front their campaigns.
- The platform: The television network, social media site or publisher whose content carries the placement. Industry codes, including the Australian Association of National Advertisers (AANA) Code of Ethics, require advertising to be clearly distinguishable as such, and platforms are expected to support that disclosure.
- Consumers: Their reaction is the legal test. Whether conduct misleads is assessed objectively, by reference to the ordinary reasonable member of the audience the campaign targets, not by whether any particular person was actually fooled.
- The regulator and the courts: The Australian Competition and Consumer Commission (the ACCC), together with state and territory fair-trading agencies, investigates complaints, issues infringement notices and can take proceedings in the Federal Court. The Federal Court decides whether conduct contravenes the ACL and, where it does, can impose penalties and other orders.
The three classic techniques
Each of the standard undercover techniques works on the same premise: the audience believes it is receiving an unsolicited opinion when it is actually receiving a paid message.
Ad spies
Ad spies are paid supporters who praise a product in public without revealing the arrangement. A business giving out samples at a market might plant a handful of people to crowd the stall, taste the product and talk it up loudly, so that genuine passers-by assume the enthusiasm is spontaneous. The same logic underpins videos in which "random shoppers" try a product and declare themselves amazed. When the people in those videos are actually employees, the audience is being told a false story about who is speaking and why.
Leaners
Leaners do the same job through conversation. They are paid to strike up casual chats in venues and social settings, steer the conversation toward the client's product and deliver a scripted "personal recommendation". The technique is harder to detect than a planted crowd because it looks like an ordinary exchange between strangers. It is also squarely aimed at creating the impression that the recommendation is genuine and unpaid.
Product placement
Product placement puts the product inside entertainment or editorial content: a character drinks a particular brand, a car features in a chase scene, a podcast host uses a specific app. Placement can be powerful because the positive feelings a viewer has for the content can transfer to the product, and the product's presence signals that other people use and value it. Whether placement is lawful depends on whether the audience understands that the appearance was paid for. Placement that audiences recognise as commercial is routine and unremarkable. Placement disguised so that the audience believes it is organic content is where the legal risk sits.
When undercover marketing becomes misleading or deceptive conduct
The core prohibition is s 18 of the ACL: a person must not, in trade or commerce, engage in conduct that is misleading or deceptive or is likely to mislead or deceive. A business running an undercover campaign is acting in trade or commerce as a matter of course, so the real question is whether the conduct is likely to mislead.
The test is objective. A court asks whether the ordinary reasonable member of the class of consumers being targeted would be likely to be misled, and it assesses the overall impression the conduct conveys rather than picking over individual words or details. That makes the framing of the campaign decisive. A campaign that presents paid promotion as organic opinion conveys a false overall impression, even if no individual statement in it is literally untrue.
Not every hidden ad is illegal. What the law catches is conduct that misleads, and the disclosure or non-disclosure of the commercial relationship is usually what determines the outcome. The ACCC's position, stated in its advertising and selling guide and its enforcement work, is that businesses must not mislead consumers by failing to disclose when an influencer has been paid to create content, whether the payment is money or free product.
Two further provisions matter. Section 29 of the ACL prohibits false or misleading representations about goods or services made "in connection with the promotion by any means" of their supply. That "by any means" wording is broad enough to capture undercover techniques. In particular:
- s 29(1)(e): catches a false or misleading representation that purports to be a testimonial by any person. An employee posing as a random customer is making a representation that purports to be a genuine testimonial, and it is false because of who is really speaking.
- s 29(1)(f): catches false or misleading representations concerning a testimonial, including presenting an edited version of a review so that it no longer reflects what the reviewer actually said.
Where the disguised promotion relates to services, s 34 of the ACL separately prohibits misleading the public as to the nature, characteristics or suitability of services. The Meriton litigation, discussed below, turned on both s 18 and s 34.
What happens when the ACCC gets involved
The ACCC can act at two levels. It can issue infringement notices where it has reasonable grounds to believe the ACL has been contravened; paying the penalty specified in a notice is not an admission of a contravention, but the notices carry real cost. Or it can take the matter to the Federal Court.
Where the Court finds a contravention of a penalty provision such as s 29, s 224 of the ACL caps the pecuniary penalty per contravention: for a body corporate, the greater of $100 million, three times the value of the benefit obtained from the conduct, or 30 per cent of adjusted turnover, and for an individual, up to $2.5 million. Section 18 itself is not a penalty provision, so a pure s 18 case produces remedies rather than fines: injunctions, corrective advertising orders, damages and declarations. In practice, undercover campaigns so often involve false testimonials or representations that the penalty provisions are frequently in play as well.
Recent enforcement shows the pattern clearly:
- In June 2026, oral care company Hismile paid $138,600 in penalties after the ACCC issued seven infringement notices over videos in which "apparently random shoppers" praised its products. The shoppers were Hismile employees. Hismile admitted its conduct was, or was likely to be, misleading, gave a court-enforceable undertaking not to present staff as random members of the public and agreed to implement a competition and consumer law compliance program.
- In March 2026, photobook business PhotobookShop paid $39,600 in penalties after the ACCC issued two infringement notices. PhotobookShop had instructed influencers on 107 occasions not to disclose that they had been given free products worth roughly $50 to $400 to create reviews, and it had substantively edited one influencer's video to remove negative comments ("a bit fiddly", "a bit confusing") so the review appeared more favourable. The ACCC alleged both practices misrepresented the reviews as organic.
- In 2018, the Federal Court ordered serviced apartment operator Meriton to pay $3 million in penalties for manipulating its TripAdvisor reviews, including by attempting to suppress negative reviews. The Court found the conduct breached s 18 and s 34 of the ACL: ACCC v Meriton Property Services Pty Ltd (No 2) [2018] FCA 1125.
Fake testimonials have been a target for a long time. The ACCC secured penalties of $215,000 against carpet cleaning franchisor Electrodry over fake online testimonials in 2015, and $600,000 against online tasking platform Service Seeking in 2020 over misleading reviews of businesses on its platform.
Common pitfalls and edge cases
The enforcement record points to the recurring mistakes businesses make:
- Employees posing as consumers: Staging "random" reactions from staff is the single most common design flaw. It converts a marketing tactic into a false testimonial, and it is the conduct the ACCC's Hismile action specifically targeted.
- Editing or deleting reviews: Removing negative content, or trimming a review so it no longer reflects the reviewer's overall impression, misrepresents the testimonial itself. That was the second PhotobookShop notice and the core of the Meriton case.
- Undisclosed gifting: A genuine influencer's review can still mislead if the audience does not know the reviewer received the product free or was paid. Disclosure is what separates an endorsement from an undisclosed advertisement.
- Over-engineering the disguise: Scripts, fake personas and staged scenarios make the conduct harder to defend. The more elaborate the concealment, the more a court will treat the overall impression as deliberately false rather than a lapse.
- Product placement in editorial content: Placement inside content that the audience treats as editorial sits in a grey zone. Whether it misleads depends on what the audience reasonably understands about the arrangement, and broadcast placement is subject to its own disclosure framework.
- Influencers as independent actors: The promoter can be pursued alongside the business. The ACCC's 2023 sweep of influencer posts found that most of the posts it examined raised concerns under the ACL, and the regulator has made clear that influencers themselves carry obligations.
Where a lawyer helps
Most of the exposure in undercover marketing is created at the design stage, which is also where legal input is cheapest.
A lawyer can review a campaign before launch against s 18 and s 29: whether the disclosure of the commercial relationship is clear enough, whether any testimonial is genuinely what it purports to be, and whether the overall impression the campaign conveys is accurate. They can draft the agreements that make compliance structural: influencer and promoter contracts with mandatory disclosure clauses, restrictions on editing reviews without consent, approval rights over final content and records of what was paid and provided. They can also build the compliance program and staff training that regulators expect to see, of the kind Hismile was required to implement.
If things go further, a lawyer handles the response to an ACCC inquiry, negotiates in relation to infringement notices, advises on undertakings, and defends Federal Court proceedings or manages the consequences of adverse findings, including corrective advertising orders and damages claims from competitors or consumers.
The cost asymmetry is worth noting. A pre-launch review of a campaign is a modest outlay. A penalty under s 224 can run to tens of millions of dollars for a corporation, before legal costs, corrective advertising and reputational damage are counted. Getting the disclosure design right early, or having a lawyer draw the line between a hidden ad and an unlawful one, is inexpensive insurance.
The risk sits in the gap between paid and organic
The pattern across every enforcement action in this area is the same. The ACCC does not police secrecy for its own sake. It polices the false impression that a paid message is an unsolicited opinion. That single distinction, between an endorsement that is disclosed and a testimonial that is disguised, decides whether an undercover campaign is a clever marketing tactic or a contravention of the ACL.
For a business considering any form of stealth marketing, the practical question is not whether the technique works. It is whether the audience would be misled about who is speaking and why. If the answer is that they would be, the campaign needs redesigning or a lawyer's advice before it runs. A short consultation to map the campaign against s 18 and s 29 is a small price to pay compared with the cost of finding out the answer from the Federal Court.