Australia’s new social media age law, which blocks anyone under 16 from using major platforms and therefore introduces online ID for all, has already become the subject of a constitutional challenge in the country’s High Court.

Reddit has filed a case arguing that the legislation undermines both privacy and freedom of expression online.

The California-based platform confirmed on Friday that it is contesting the Social Media Minimum Age (SMMA) law.

We obtained a copy of the filing for you here.

The company said that while it agrees on the need to protect younger users, the government’s chosen method is overly invasive.

In a statement, Reddit said the law “carries some serious privacy and political expression issues for everyone on the internet” and imposes “intrusive and potentially insecure verification processes on adults as well as minors.”

Under the SMMA law, which began this week, global platforms such as TikTok, YouTube, Instagram, Snapchat, and Reddit must delete accounts belonging to Australians under 16.

Those that fail to comply can face penalties of up to 49.5 million Australian dollars, roughly 33 million US dollars.

Julie Inman Grant, Australia’s “eSafety” Commissioner, has started enforcing the new policy by sending formal notices to ten companies requiring details on how many underage profiles they have already removed.

Her office plans to request updates every six months to measure compliance. She previously said she expected some social media companies to wait for enforcement action or fines before taking legal steps against the law.

In its application, Reddit seeks “a declaration that the Online Safety Amendment (Social Media Minimum Age) Act 2024 (Cth) (Amendment Act) is invalid” and an order restraining the Minister from designating Reddit as an age-restricted service.

The company makes clear that the consequences are sweeping: the Act “prohibits all Australians under the age of 16 from engaging in any political communication on an ‘age-restricted social media platform’ to the extent that such communication requires an account.”

Reddit argues that the law imposes a “direct and substantial, or alternatively deep and wide” burden on political speech, noting the obvious reality that “the mode that is affected is an extremely important one in Australia in 2025” given that “there are many subreddits dedicated to discussion of Australian political matters” and that elected representatives “frequently” use the platform to engage with constituents.

The platform also highlights the Minister’s explicit intention to capture Reddit under the new law, pointing to the Second Reading Speech where “the government expects that this broader definition will capture services that are commonly accepted to be social media, which will, at a minimum, include … Reddit.”

The eSafety Commissioner, it notes, has similarly concluded that “Reddit is an ‘age-restricted social media platform’.”

Yet Reddit contends the Act is internally inconsistent and ineffective. The only requirement imposed on platforms is to “take reasonable steps to prevent age-restricted users having accounts,” but crucially, “the Amendment Act does not impose any obligation on providers to restrict access to content on the site that is accessible without an account.”

In Reddit’s case, this is decisive: “almost all of the content on the site is accessible without an account.” As a result, the filing argues, the law “will not provide significant protection from online harm for persons under the age of 16.”

The company even insists the Act may worsen the situation it claims to solve. According to the filing, “a person under the age of 16 can be more easily protected from online harm if they have an account, being the very thing that is prohibited.”

Reddit also attacks the statute on proportionality grounds, arguing there exists an “obvious and compelling alternative” in a law limited to services where “the substantial proportion of the functionality is accessible only with an account,” unlike Reddit, where content remains broadly visible to the public.

Even if the Court upholds the Act, Reddit argues it should not be classified as an age-restricted social platform in the first place. The statutory test requires that “the sole purpose, or a significant purpose, of the service is to enable online social interaction between 2 or more end-users.”

Reddit insists this does not describe its service, and that the term “social” is doing meaningful work. The company stresses that “it is not the sole or a significant purpose of Reddit to enable persons to interact ‘in a social manner’,” noting that “in most cases the identity of a user on Reddit is not even known to other users.”

Rather than fostering personal relationships, Reddit “facilitates knowledge sharing from one user to other users,” which it argues is materially different from platforms built around friendship networks, personal profiles, or events.

Even the chat feature does not change this conclusion, Reddit says, because it “is not intended to facilitate what would ordinarily be described as ‘social’ messaging” and in any case “cannot properly be characterized as a ‘significant’ purpose of Reddit.”

The High Court will hold a preliminary session in February to decide how and when Reddit’s challenge will be heard.