Google and Meta reportedly struck a secret deal to target underage YouTube users with advertisements that promoted rival service Instagram – breaking the online search giant’s own ad rules, according to a bombshell report Thursday.

 The Instagram ad campaign was aimed at YouTube users who were classified as “unknown” in Google’s ad system and designed to appeal to users aged 13 to 17, the Financial Times reported, citing internal documents and people familiar with the matter.

The report said Google was aware that the “unknown” user category skews toward those under 18 but allowed the campaign anyway. On its website, Google defines the “unknown” category as referring to users “whose age, gender, parental status, or household income we haven’t identified.”

Internal documents obtained by the outlet reportedly showed that employees tried to disguise the campaign’s true goal of reaching underage users. Google has banned ads targeting under-18 users based on age, gender or interests since 2021.

The two companies launched the US ad campaign in May after earlier trials in Canada, the report said. They reportedly partnered with Spark Foundry, an agency that’s a subsidiary of ad juggernaut Publicis.

One email from and ads manager at Spark asked Google to pitch for the campaign, specifically identifying the “primary” demographic to be targeted is “13 to 17” year-olds, FT reported.

The fierce Big Tech foes apparently had their own motives for the surreptitious pact, with Google seeking to boost advertising earnings and Meta scrambling to prevent younger Instagram users from flocking to popular video-sharing app TikTok, according to the publication.

Sources told the FT that Google launched an investigation into the allegations after being contacted by the outlet and has since canceled the campaign.

“We prohibit ads being personalized to people under 18, period,” a Google spokesperson said in a statement. “These policies go well beyond what is required and are supported by technical safeguards.”

“We’ve confirmed that these safeguards worked properly here,” the spokesperson added. “We’ll also be taking additional action to reinforce with sales representatives that they must not help advertisers or agencies run campaigns attempting to work around our policies.” 

A Meta spokesperson said the company has “been open about marketing our apps to teens as a place for them to connect with friends, find community, and discover their interests.”

“Google’s “unknown” targeting option is available to all advertisers — not just Meta — and we have clear principles we adhere to when it comes to how we market our apps to teens on other platforms, including not using information about their interests to target them with ads,” the Meta spokesperson added.

Spark Foundry did not immediately return a request for comment.

Google and Meta reportedly hatched the plan at the end of last year – meaning it was already underway when Congressional lawmakers confronted Facebook founder Mark Zuckerberg over the company’s failure to protect kids from online harm.

During a dramatic hearing in January, Zuckerberg publicly apologized to the families of victims of online child sex abuse.

Late last month, the Senate passed a landmark bill called the Kids Online Safety Act, which would enact a legal “duty of care” requiring social media companies like Instagram and YouTube to protect underage users – or face enforcement action by the FTC.

A companion bill, the Children’s and Teens Online Privacy Protection Act, or COPPA, blocks targeted ads aimed at underage users and would mandate creation of an “eraser” button on social media sites allowing kids and parents to delete information.

“Big Tech companies cannot be trusted to protect our kids,” Republican Sen. Marsha Blackburn, who co-sponsored the KOSA bill, told FT after learning of the Google-Meta scheme.

“They once again have been caught exploiting our children and these Silicon Valley executives have proven that they will always prioritize profit over our children.”

Jeff Chester, executive director of the Center for Digital Democracy, which advocates for child privacy, told the outlet: “Meta is bleeding young people and they’ve figured out a backdoor.”

Both pieces of legislation face an uncertain road to final passage in the House.

Meta is currently being sued by dozens of state attorneys general who have accused the company of building addictive apps that exploit teens for ad revenue at the expense of their mental health.

Separately, the state of New Mexico is suing Meta for allegedly failing to protect kids from being contacted by alleged sex predators.

The company has repeatedly denied wrongdoing and touted its efforts to implement safety tools and resources for kids and parents active on its platforms.

Google was dealt a major regulatory blow earlier this week after a federal judge ruled the company has maintained an illegal monopoly over online search. Court proceedings to determine appropriate remedies are set to begin this fall.

Google also faces a federal antitrust lawsuit targeting its digital advertising technology business.