HiSmile Lawsuit: False Advertising Claims and Court Ruling

The HiSmile lawsuit that drew the most attention, a proposed California class action over the brand’s viral teeth-whitening ads, was dismissed with prejudice in April 2026 after a federal judge ruled that HiSmile’s “instant teeth whitening” pitch is non-actionable puffery rather than a measurable promise a reasonable consumer could rely on. A parallel proposed class action was filed in the Central District of California around the same time. Outside court, HiSmile fared worse: U.S. advertising self-regulators found several of its claims unsupported and referred the company to the Federal Trade Commission, and in June 2026 Australia’s consumer regulator fined the company A$138,600 for misleading social media videos.

The Two U.S. Class Actions and What They Claimed

Two proposed class actions were filed in California federal courts in June 2024. Jimenez v. HiSmile, Inc. was filed on June 6, 2024, in the Central District of California by four named plaintiffs.{¹} Ledesma v. HiSmile, Inc. followed on June 14, 2024, in the Northern District of California, brought by two Bay Area buyers who said they had spent between $27 and $35 on HiSmile products.{²}

Both complaints targeted the same four products: the V34 Colour Corrector Serum, Glostik Tooth Gloss, PAP+ Whitening Strips, and the PAP+ Whitening Pen. Both raised the same five California-law claims: violations of the Unfair Competition Law, the False Advertising Law, and the Consumers Legal Remedies Act, plus breach of warranty and unjust enrichment.{¹}{} The core theory was that HiSmile ran what the Ledesma complaint called an “aggressive, pervasive, and fraudulent social media marketing” campaign to conceal that its products do not meaningfully or durably whiten teeth.{} The complaints alleged the V34 serum was marketed as “clinically proven” to whiten teeth instantly despite never having been clinically tested, and that HiSmile’s PAP-based products were sold as “just as effective as hydrogen peroxide” even though studies cited by the plaintiffs found PAP far less effective than peroxide bleaching agents.{²}

How the Court Ruled

The Ledesma case produced the substantive rulings. At a July 17, 2025 hearing, U.S. Magistrate Judge Kandis A. Westmore expressed skepticism that the complaint identified which specific ads or representations had induced the plaintiffs to buy. HiSmile called the claims “implausible,” pointed to “results may vary” disclaimers, and asked for dismissal with prejudice. Plaintiffs’ counsel at the Clarkson Law Firm responded that HiSmile’s algorithmic social media strategy produced “seemingly infinite variations” of video clips, making it unrealistic to require consumers to recall specific ads, and invoked the California Tobacco II doctrine, which can excuse plaintiffs from pinpointing individual ads within a long-running, pervasive campaign.{³}{⁴}

On September 23, 2025, Judge Westmore granted HiSmile’s motions to dismiss and struck the proposed nationwide class allegations, ruling that the complaint failed to meet the heightened pleading standard for fraud. The court acknowledged that the Tobacco II exception might apply to algorithmic social media marketing, but said the complaint lacked specifics on the campaign’s duration, each plaintiff’s exposure, and which endorsements or reviews were false. Dismissal came with leave to amend.{⁴}

The plaintiffs filed a Second Amended Complaint on October 23, 2025, adding detail about the campaign’s ten-year duration and each plaintiff’s exposure on particular platforms. It wasn’t enough. On April 28, 2026, Judge Westmore dismissed the case with prejudice, holding that HiSmile’s core “instant teeth whitening” marketing claim is non-actionable puffery, not a quantifiable representation a reasonable consumer would rely on. Because it was the third version of the complaint and the court concluded the underlying legal theory could not be saved, the plaintiffs got no further chance to amend.{⁵}

What the Ads Were Accused of Doing

Even though the case did not survive, the complaints laid out a detailed picture of the marketing practices at issue. The plaintiffs alleged HiSmile applied brown solution to models’ teeth and wiped it away with the product to fake dramatic color change; showed the purple V34 serum sitting on teeth to create an illusion of “color correction” that disappeared when rinsed; and stained already-white teeth before demonstrating PAP+ strips removing that surface discoloration.{⁴} Bright lighting and models with already-very-white teeth were used in filming, and “dramatizations” involved yellow objects such as bananas and rubber ducks painted purple to illustrate color theory in ways the plaintiffs said had nothing to do with removing actual stains.{²}

The complaints also accused HiSmile of fabricating five-star Amazon reviews, singling out a Glostik review from “Jason,” whom the plaintiffs identified as an actor-employee appearing in the company’s marketing videos. HiSmile employees allegedly posed as regular consumers in social media clips and staged responses to TikTok comments the plaintiffs said were not real. Negative reviews were said to be removed from the company’s own website. Kim Kardashian, Kylie Jenner, and Conor McGregor were named as paid endorsers whose promotional posts allegedly lacked proper advertising disclosures, with the complaints noting that the celebrities’ white teeth came from professional dental work rather than HiSmile products. Actors were also accused of appearing in lab coats and dental scrubs to look like scientists or dental professionals.{⁴}{²}

NAD Findings and FTC Referral

Outside of court, HiSmile drew adverse findings from the National Advertising Division of BBB National Programs. In a decision released April 11, 2024, prompted by a challenge from Procter & Gamble (which makes Crest), the NAD recommended HiSmile discontinue safety claims that peroxide-based whiteners are “painful” or “damage” teeth and gums, and the comparative claim that HiSmile’s products are “just as effective as hydrogen peroxide.” The NAD said HiSmile provided no evidence supporting those assertions. HiSmile dropped one claim voluntarily and said it would appeal the rest.{⁶}

In a separate proceeding, the NAD recommended HiSmile stop using “instant brightening” and “clinically proven instant whitening” claims, drop assertions of “no tooth sensitivity” and “no gum irritation,” modify misleading product demonstrations (including the egg and banana demos), and make influencer disclosures clear in both audio and video rather than relying on small platform labels.{⁷} HiSmile did not follow through on its appeal, ultimately declining to participate in the self-regulatory process or confirm compliance.{⁸} The NAD referred the matter to the FTC and other regulators for potential enforcement.{} Whether the FTC has acted on that referral is not publicly known.

The Australian Regulator’s Fine

In HiSmile’s home country the regulator moved directly. On June 12, 2026, the Australian Competition and Consumer Commission issued HiSmile seven infringement notices for false and misleading representations in social media advertising, and the company paid A$138,600 in penalties.{⁹}

The ACCC found that HiSmile used employees who posed as “random shoppers” in promotional videos and misleadingly implied that its Glostik Tooth Gloss could remove tooth stains when it only provided temporary concealment. HiSmile admitted its conduct was, or was likely, misleading under Australian Consumer Law, and the Glostik product has since been discontinued.{¹⁰} Under a court-enforceable undertaking, HiSmile agreed to stop presenting staff as random members of the public, implement a compliance program, publish notices about the ACCC’s action on its website and social media, and stop claiming its products produce permanent results when they don’t.{⁹}

Do the Products Actually Whiten Teeth?

HiSmile’s whitening products use phthalimidoperoxycaproic acid (PAP) as the active ingredient, marketed as a peroxide-free alternative to hydrogen peroxide and carbamide peroxide.{⁶} A 2023 in-vitro study in Dentistry Journal tested a HiSmile kit on bovine teeth stained with coffee, tea, wine, and curry and found that while the kit produced a measurable color change, it was less effective than a conventional carbamide peroxide control.{¹¹} A second 2023 study, in International Journal of Molecular Sciences, compared 12% PAP against 6% hydrogen peroxide and found hydrogen peroxide significantly more effective; the authors concluded only hydrogen peroxide could whiten natural enamel, while PAP merely removed surface stains.{¹²}

The V34 Colour Corrector Serum, HiSmile’s most viral product, works on a different principle: purple dye that visually neutralizes yellow tones through color theory rather than bleaching. The effect is cosmetic and temporary, typically lasting a few hours before eating, drinking, or brushing washes it off.{¹³} An Australian dental practice that tested V34 concluded it made “no difference at all to the colour or brightness” of teeth and said it could not recommend purchasing it.{¹⁴}

1
ClassAction.org. Jimenez et al. v. HiSmile, Inc. Complaint
2
Courthouse News Service. Ledesma et al. v. HiSmile Complaint
3
Courthouse News Service. Judge Skeptical of False Advertising Claims Against Viral Teeth Whitener
4
FindLaw. Ledesma et al. v. Hismile, Inc.
5
Justia. Ledesma et al. v. Hismile, Inc.
6
BBB National Programs. HiSmile Appeals
7
Yahoo Finance. National Advertising Division Refers HiSmile
8
Legal Reader. NAD Refers Comparative Efficacy Claims for HiSmile to Regulatory Authorities
9
Nine News. HiSmile Viral Oral Care Company Slapped With Major Fine for Misleading Social Media Videos
10
ICPEN. ACCC Action Against HiSmile
11
PubMed Central. In Vitro Evaluation of Tooth-Whitening Potential of Peroxide-Free OTC Dental Bleaching Agents
12
PubMed Central. Comparative Study of OTC Whitening Agents
13
Innerbody. HiSmile Reviews
14
Dental Quarters. HiSmile V34 Colour Corrector Serum Review