Participants hold signs in support of TikTok outside the U.S. Capitol Building on March 13, 2024 in Washington, DC.Getty ImagesTikToks social media rivals are set to pounce but exactly which one will win remains an open question.Domestic tech firms now stand to greatly benefit following Fridays Supreme Court decision declining to overturn the federal law that will see TikTok removed from app stores on Sunday over national security concerns.Industry analysts like EMarketer determined earlier this month that Meta, which owns Facebook, Instagram and Threads, along with Alphabet, which owns YouTube, could capture around half of the ad dollars that might flee TikTok once the app goes dark. (The entire American annual social media ad spend in 2024 was around $80 to $90 billion, according to EMarketer.)Still, its not a done deal: Once inaugurated, President Trump could grant TikTok a reprieve while it looks for a buyer, fulfilling his promise to save the app for a short while. If and when TikTok is fully banned, it will be hard for any rival to completely capture the apps userbase."Its not that these companies havent been trying to pick up TikTok users there is something about how the service works that makes it hard to duplicate, Jim Lewis, the senior vice president of the Center for Strategic and International Studies, told Forbes.TikTok CEO Shou Zi Chew testifies before the House Energy and Commerce Committee in the Rayburn House Office Building on Capitol Hill on March 23, 2023 in Washington, DC.Getty ImagesImplementation of the federal law now forbids American companies from doing business with TikTok starting on Sunday. A ban would last until the Chinese-owned ByteDance, TikToks parent company, sells its U.S. division to an American firm. So far, numerous buyers ranging from Elon Musk to Mr. Beast, the popular YouTuber, have been floated but none have materialized.The Biden administration has said that it would not enforce the law in the waning hours of its tenure. White House Press Secretary Karine Jean-Pierre said Friday that actions to implement the law simply must fall to the next Administration, which takes office on Monday at noon Eastern Time.ByteDance, TikToks parent company, did not respond to Forbes repeated request for comment.In a TikTok video released Friday, CEO Shou Zi Chew called the law arbitrary censorship, and added his thanks to President Trump for his commitment to work with us to find a solution that keeps TikTok available in the United States.If you had a dollar, where would you see the most upside? If you invested it in Meta or Snap, all else equal, the Snap dollar should appreciate more.TikTok has captivated the attention of millions of Americans in recent years. Pew Research found in December 2024 that approximately one-third of U.S. adults use the app. Nineteen percent of American teen girls say they use it almost constantly. Analysts have found that the average 18- to 24-year-old TikTok user spends nearly 80 minutes per day on the app.The question is: where will they go?The hypothesis is that people will go somewhere else to scratch the same itch, said Evan Horowitz, the CEO of online ad agency Movers+Shakers, who has been preparing its clients to translate their TikTok videos to other platforms. Its not like the traffic will go to Twitter as thats a different form. YouTube Shorts skews younger, while a millennial is more likely to prefer Instagram and Reels.Benjamin Black, the co-head of internet equity research at Deutsche Bank, told Forbes that one rival is poised to see the most relative benefit: Snap.Because Meta is a significantly larger company (around $1.55 trillion market capitalization) relative to Snap (around $20 billion market capitalization), even a small bump for the Santa Monica-based app would translate into a much greater relative revenue.Most people assume that Meta is going to get the lions share, but given the size of Snap, even if it gets 10% or so of TikToks minutes, and they monetize it at traditional Snap rates, that would have huge ramifications for the business in a positive way, Black said.If you had a dollar, where would you see the most upside? If you invested it in Meta or Snap, all else equal, the Snap dollar should appreciate more.Snap has been preparing for TikTok to go offline for months. In September, the company announced Simple Snapchat, an app redesign debuting later this quarter thats clearly meant to mimic TikTok. Simple Snapchat would have what the company called its first-ever unified recommendation system, which eliminates some the Snap Map and Stories tabs, making it much closer to a TikTok-like design where short-format videos immediately load.Snapchat on the App Store displayed on a phone screen and a laptop keyboard are seen in this illustration photo taken in Krakow, Poland on August 10, 2022.NurPhoto via Getty ImagesOther ad firms are also looking at redistributing their spending to other kinds of social media apps, and not just ones that mimic TikToks style and format.Were also considering platforms like Pinterest and Reddit who have a strong social search presence and search targeting functionality, enabling us to stay agile in capturing real-time conversations and demand, Toni Box, the executive vice president of brand experience at Assembly Global, a media agency, emailed Forbes.Also in the mix are Chinese apps like Xiaohongshu, also known as RedNote, which has a similar short-form video format and saw an influx of so-called TikTok refugees this week as it shot to the top of the app store downloads. . But if it grows quickly enough, it could ultimately face a similar ban.Unlike TikTok, RedNote does not have a separate U.S. app, which poses similar, if not more serious, issues for lawmakers concerned about user privacy and national security, Jasmine Enberg, an analyst at EMarketer, emailed Forbes.Whats clear is that the law doesnt solve the problems that lawmakers have said it is aimed to fix. Its narrow scope (ie. singling out ByteDance and TikTok) doesnt address the larger privacy and security risks on social media, posed by both U.S. and foreign-owned apps.MORE FROM FORBES