In a rare digital privacy verdict, an eight-person San Francisco federal jury held in August 2025 that Meta illegally eavesdropped on millions of women who entered menstrual and pregnancy health data into the Flo Period and Ovulation Tracker app (Flo app), finding that the social media giant had violated the 1967 California Invasion of Privacy Act (CIPA). Hundreds of lawsuits about websites and apps have invoked the law, originally enacted to protect consumers from unauthorized recordings of phone calls.
The case’s substantial implications are strongest for the roughly 500 CIPA lawsuits involving health information, which have been more successful in pretrial stages than other case types, reported Tammana Malik, an attorney at Troutman Amin. “Courts are taking a stricter approach when it comes to health information cases,” she told the Cybersecurity Law Report. “It’s an area where we have seen the plaintiffs doing really well.”
The jury reached conclusions on the core issues of “eavesdropping” and expectations of confidentiality running through CIPA case law. If Meta’s promised appeals fail, it could end up paying hundreds of millions of dollars, thanks to the law’s $5,000 statutory damages fine for each affected Californian. The verdict warns the multitudes of companies that receive data from a software development kit (SDK) in a mobile application that they could have CIPA liability.
This article, the first in a two-part series about CIPA lawsuits, examines how the plaintiffs persuaded the jury that Meta intentionally eavesdropped on them without consent, and the dynamics of trying privacy cases before a jury, with commentary from privacy litigators at Farella, Braun & Martel, Holland & Knight and Troutman Amin, and from an attorney who reached a $725‑million settlement with Meta. Part two will discuss the implications of the verdict for other CIPA disputes and examine other important 2025 CIPA court decisions.
See “Lessons From the Trenches: Winning Strategies for Defeating Pen Register Lawsuits” (Jun. 12, 2024).
How Plaintiffs Made It to Trial
Plaintiffs filed the case in 2021, based on a Wall Street Journal 2019 investigation and an FTC enforcement action against Flo Health, Inc. (Flo). The plaintiffs argued that Meta was liable for receiving information between June 2016 and February 2019 about their menstrual cycles, pregnancy goals and 10 other details about reproductive health that Flo’s app transmitted using Meta’s SDK.
In the Court’s May 2025 class certification and summary judgment decisions, it held that several disputed points in the case belonged with a jury. These included whether intentional eavesdropping occurred and whether users consented to allow Meta to “record” interactions with the Flo app.
As trial approached, Meta had two co-defendants, but fellow Big Tech monolith Google settled two weeks before opening arguments. The parties have not disclosed terms. A fourth defendant, defunct mobile analytics company Flurry, settled with plaintiffs for $3.5 million in March 2025. Flo and Meta then opted to risk a giant verdict for the possibility of cementing CIPA defense arguments as winning precedents.
See “Google’s Wiretap Cases Highlight Evolving Privacy Transparency Standards” (Jan. 24, 2024).
The Playing Field for a Trial of App Users Versus Tech Companies
The plaintiffs’ attorneys had a few strategic advantages for a trial presenting five women as the victims of prominent technology companies that care more about ad placements than whether users consented to share personal data, raising questions about Meta’s gamble on a jury over settlement.
The Bay Area Jury
The defendants had some reason to be confident. In the Bay Area, some sets of jurors can be problematic for privacy plaintiffs litigating against Big Tech companies, Bleichmar Fonti & Auld partner Lesley Weaver told the Cybersecurity Law Report. “Lawyers may face cynical jurors who say, ‘I assume everybody’s taking everything data-wise. I don’t believe anything anybody says.’ The plaintiffs have to win over that juror,” she reported.
The plaintiffs’ lawyers may also face Bay Area jurors who are “tech defenders,” Weaver continued. Meta’s post-trial motion highlights this demographic, with a twist. The defendant contends that the Court should have excluded “Juror #4” because that juror stated that he was friends with a WhatsApp founder who publicly disagreed with Facebook after it acquired that popular messaging app.
Highly Sensitive Data in the Courtroom
The plaintiffs had the intimacy of menstrual data as a sympathy point to anchor their arguments, Malik noted. Risks around reproductive health information have been widely discussed since the Supreme Court’s Dobbs decision about abortion rights, including state prosecutors’ vows to use menstrual and pregnancy information to investigate abortions, she observed.
Privacy concerns also have deepened culturally, Farella Braun partner Sushila Chanana observed, as people’s use of “health applications has increased drastically over the past five or six years. [Data breaches have] also increased in that time. They are always in the news. Consumers are just thinking about personal data more,” she told the Cybersecurity Law Report.
Public awareness of third-party data sharing for advertising has grown with the expansion of cookie banners, Chanana continued. “Consumers today are more aware of the consequences of poor data management and expect businesses to be transparent about data collection and usage practices – especially when it comes to sensitive health information,” she said.
A Strong Promise Unfulfilled
Plaintiffs litigating a data privacy case almost always show the jury a broken promise. The second crucial exhibit they must show is technical evidence of mishandled data.
In this trial, the plaintiffs spotlighted a commitment in Flo’s 2018 privacy policy, which indicated that the app might share users’ information with third parties if “reasonably necessary to perform their work,” such as supplying software applications and web hosting. The policy clarified, however, that it would “exclud[e] information regarding your marked cycles, pregnancy, symptoms, notes and other information that is entered by you and that you do not elect to share.”
“Plaintiffs are more likely to win in a privacy case where a defendant breached an express promise not to do something by then doing it. That’s what happened here,” explained Weaver, who won a $15‑million jury verdict in 2014 against a website that shared information about users’ sexually transmitted disease status, and then, in 2024, helped plaintiffs reach a $725‑million settlement with Meta for sharing data with Cambridge Analytica.
Plaintiffs needed to prove that their menstrual and pregnancy information traveled to Meta using its SDK. Courtroom jousting by expert witnesses over data transmissions and “app events” can implicitly help plaintiffs’ case – the jury’s effort to decipher the technical details underscores the plaintiffs’ predicament with consent. “The asymmetry in knowledge between what the companies are doing with data and what the average person understands is happening is a gap that has closed in recent years, but it’s still immense,” Weaver highlighted.
See “Why Companies Unintentionally Fail to Honor Opt-Outs” (Aug. 16, 2023).
The Complications of Two Defendants
The plaintiffs had a procedural advantage at trial. The Court had allowed them to move forward with multiple legal claims against Flo, but only a CIPA Section 632 claim against Meta. Plaintiffs’ attorneys had the advantage of presenting evidence against two defendants, telling a fuller story. In contrast, the two defendants were at risk of fragmenting their arguments to address different claims.
Flo settled before final arguments. The parties did not disclose that settlement’s financial terms. That left Meta to face a jury without an app owner to absorb blame for breaking its promise to users.
Meta’s attorneys decided to move forward with the federal jury, facing the risks of defending itself as the deep pockets quietly receiving the data as a third party. “Meta has much more at stake than any individual app owner or web developer,” pointed out Holland & Knight partner Ashley Shively. “This SDK is fundamental to Meta’s business and how it makes money,” so it has incentive to defend it to the last, she added. Perhaps the trial risk was worth the gamble to Meta, which has the resources to look past the jury to appellate judges who may be skeptical about applying a 1960s law to today’s technology.
See “Defense and Plaintiff Perspectives on How to Survive Data Privacy Collateral Litigation” (Mar. 8, 2017).
The Disputed Points in the Trial
The trial delivered an unusual courtroom spectacle of privacy victims and a privacy engineer testifying about the governance of intimate personal data, as well as cross-examinations raking over a few insensitive internal employee comments about personal data. In its defense, Meta tried to combat unflattering facts about notice and consent, and to downplay its control over its SDK’s actions.
The CIPA claim before the jury required it to answer the following questions:
- Did Meta intentionally eavesdrop on plaintiffs’ conversations on an electronic device?
- Did plaintiffs prove they had a reasonable expectation that the conversation was not being overheard and/or recorded?
- Did Meta have the consent of all parties to the conversation to record it?
Eavesdropping, or Passing Secondhand Information?
The jury’s central factual decision to make was whether Meta’s SDK directly recorded plaintiffs’ communications. The plaintiffs’ experts claimed that the SDK listened in the background while women typed in the Flo app, then sent to Meta the records of women’s answers to 12 Flo questions about pregnancy or menstruation details, such as last period date and length of menstrual cycle.
To counter the eavesdropping accusation, Meta strove mightily to persuade the jury that its SDK relayed a “secondhand” version of the women’s typed information rather than listening secretly to obtain a word-for-word version of a communication, the way a spy’s classic wiretap does. Only Flo “heard” the details, Meta’s engineers testified, further explaining that the Meta SDK “generated” a separate summary that did not match exactly what the women typed in the app.
The defendants “were relying on very technical discussions about how the SDK is integrated into the app code and the timing of separate transmissions” between user and app, and then app and Meta, Shively noted. This was “to try and lead the jury to the conclusion there was no eavesdropping or that this data was not confidential. And that’s incredibly challenging,” she said.
See “Facebook Wiretap Ruling Inspires Slew of Lawsuits Over Consumer Tracking” (Dec. 2, 2020).
Intentional Data Collection, or Accidental and Unwanted?
Meta claimed it did not “intentionally” seek the menstrual data, emphasizing its passivity throughout the process. Apps like Flo configured Meta’s free, open-source SDK as they wanted, choosing the app events to send to Meta for its ad services. Meta imposed almost no requirement about the information it wanted from apps for ads, nor did it need all the information Flo sent about the users, the company’s defense insisted.
Meta’s defense counsel showed the jury two letters that it sent Flo warning that its app had improperly sent forbidden PII to Meta, violating its terms of service for business tools, including the SDK.
“Meta was trying to walk this tightrope in their defense strategy, both blaming the app developer for sending data that Meta claims it never wanted and downplaying the significance of the data, saying it was minimal and limited,” Shively said.
The second part of the Court’s jury instruction around intent snared Meta, however. Intentional eavesdropping reflects either a defendant’s “purpose or desire” to record a confidential conversation or that the defendant acted “with the knowledge to a substantial certainty that his use of the equipment will result in the recordation of a confidential conversation,” according to the instruction.
Inspired by the second prong of the definition of “intent” in the jury instruction, the plaintiffs highlighted that Meta crafted its SDK to ingest information about users’ statements. This underscored that “the Facebook SDK was doing the transmission, not the Flo app,” Weaver said. The plaintiffs’ presentation about the SDK’s operations reinforced that Meta wanted it nestled inside the app, like a bug on the phone line. “After you spend some time with the details, it becomes very clear to people what’s going on,” she underlined.
See our four-part series on tracking technologies: “Privacy Regulation, Enforcement and Risk” (Jan. 17, 2024), “A Deep Dive on What They Are and How They Work” (Jan. 31, 2024), “A 360‑Degree Governance Plan” (Feb. 21, 2024), and “Compliance Challenges and Solutions” (Apr. 17, 2024).
Expectation of Confidentiality, or Knowledge of Recording?
Meta made a technical point in its post-trial motion, arguing that the plaintiffs could not expect confidentiality because their “entering information into a period and pregnancy tracking app suggests that the information was ‘by nature recorded’ by the app.”
Defendants like Meta have grounds to keep battling the plaintiffs’ arguments that wiretapping law fits with online tracking technologies, Shively opined. “Most of the authority on confidentiality comes from call recording cases, like a case 20 or so years ago about an ex‑spouse listening to their significant other in the next room. None of the law has been developed in the context of internet activity communications,” she pointed out.
Meta cast the SDK’s transmissions as prosaic operational data to be used for automated advertising. Plaintiffs’ attorneys in privacy cases often seek to translate for the jury the experts’ terminology, Weaver noted. “Everyone calls it ‘data,’ which is clinical. But it’s not data, it’s information, and information about you that can be stitched together for all kinds of purposes,” she said.
The plaintiffs in this Meta case were able to argue that they expected confidentiality because the case involved intimate health data, Shively noted. In a similar suit involving an e‑commerce or retail company facing CIPA claims, plaintiffs’ expectation of confidentiality argument might not hold up because the unauthorized revelation of purchasing information seems less harmful than menstrual data, she said.
Consent to Share Menstrual Information, or Insufficient Boilerplate?
The two-part jury instruction for assessing the plaintiffs’ consent was defendant friendly. It defined plaintiffs’ consent as either affirmative, sufficiently clear words or acts, or implicit approval. “A plaintiff may also express consent by silence or inaction if a reasonable person would understand that the silence or inaction intended to indicate consent,” according to the instruction.
The jury rejected Meta’s contention that the plaintiffs’ agreement to boilerplate Facebook terms of service sufficed as their specific consent to share this personal information. Meta disclosed it received data about user activity on third-party apps and may use the information for advertising. Plaintiffs’ counsel stated in the closing argument that, to constitute consent, Meta’s policy needed to specify that it might gather “private health information” or cull data from “fertility apps.”
Furthermore, Flo’s privacy policy (during the class period) mentioned sharing PII with Facebook and other third parties but also said that it did not rent or sell information without the user’s consent.
See “Practical Strategies for Effective Consent Management” (Sep. 25, 2024).
Contents of the Communication, or Just Data Points?
To succeed under CIPA Section 632, the plaintiffs had to prove that the “contents of their communication” were intercepted by Meta, as opposed to just “the record” of the communications, Malik noted.
Perhaps influencing the outcome, the jury instructions listed 12 data points that app users entered in the app and Meta received. Flo’s names for the data points included “R_SELECT_PERIOD_LENGTH” and “R_PREGNANCY_WEEK_CHOSEN,” among other pregnancy and menstruation details. “The custom event labels probably had an impact on the case,” persuading the Court and the jury that Meta was receiving the “contents of a conversation” rather than just a scattering of data points that simply served as a record of the communications, Malik posited.
See “Sale of 23andMe’s Genetic Data: Lessons for Companies Around Sensitive Data” (Apr. 23, 2025).
Post-Trial Motion
After trial, Meta filed a motion under Rule 50(b) arguing that the evidence in trial allowed only one conclusion, of no violation. The company reiterated its trial arguments that evidence showed no “eavesdropping,” “recording,” “intentionality” or “confidentiality.”
Meta requests that, “at minimum,” the Court order a new trial. The Court made a critical error in the jury instruction about intent, issued erroneous evidentiary rulings and wrongly seated an admittedly biased juror, Meta asserts, adding that each error independently warrants a new trial. Plaintiffs argued in their opposition, filed August 21, 2025, that “the jury was well within its right” to make its findings about eavesdropping, recording, intent and confidentiality.
The Statutory Damages Decision
If the Court denies Meta’s motion, it will then decide damages. The plaintiffs seek damages treating each member of the California class of plaintiffs as a single CIPA violation, Meta’s trial brief states. If the Court adopts that approach, “the number of unique California individuals would be the key inquiry,” said Shively.
The trial documents do not break out the number of Californians whose data was transmitted. The SDK transmitted to Meta data points about menstrual cycle length for more than 31 million individuals; California has 12% of the U.S. population.
Data reflecting users’ responses to the app was deleted in the normal course before litigation, Shively noted. Thus, the Court and parties lack shared evidence to determine which class members have a viable claim and may be entitled to damages. For an individual to be considered a member of the class with a viable claim, she will need to show that (1) she joined the app during the class period, (2) while physically present in California, and that she (3) shared “sensitive” information during the signup process, and (4) suffered a compensable injury resulting from the data shared with Meta.
“Meta makes a compelling case that resolving these questions will require an individual inquiry” for each member, Shively opined. Meta has a right to cross-examination, so it is unlikely to accept a self-attesting claims process.