Polymarket claims that several new products launched by Kalshi bear a high similarity in launch timing and product design to Polymarket, with coincidences that are unusual.

Written by: Marc Vartabedian, New York Post

Translated by: Luffy, Foresight News

The prediction market platform Polymarket is conducting an in-depth investigation into a suspected case of competitive corporate espionage. The platform allows users to bet on sports events, weather, and geopolitical issues. The company accuses its primary competitor Kalshi of stealing commercial information and imitating products through improper means.

This prediction platform, headquartered in New York, is led by 27-year-old CEO Shayne Coplan. They have compiled a verification document titled "Plagiarism File," which includes more than a dozen questionable incidents: the launch timing and product design of several new products by Kalshi are highly similar to Polymarket, with release coincidences that are unusual.

Polymarket's market manager Matthew Modabber stated in a phone interview that the coincidences are truly numerous to the point of being unusual, and that the other party's intent to plagiarize is very strong, steadily threatening our business.

Polymarket CEO Shayne Coplan spoke at the New York Stock Exchange on November 13 last year

The executive did not disclose more details, but insiders revealed that the company internally suspects two possibilities: one is that there is an insider planted within Polymarket; the other is the more bizarre suspicion of surveillance.

In recent months, multiple employees have suggested that Kalshi's investor Paradigm is suspected of surveilling Polymarket's office in Lower Manhattan from across the street. Paradigm's office in Soho, New York, is directly opposite Polymarket's office, with floor-to-ceiling windows that can directly view the Polymarket workspace, and may even observe employees' computer screens. The ground floor facing the street features a trendy clothing store and the upscale restaurant Balthazar.

Due to concerns about surveillance, Polymarket specially applied dark heat-insulating film to the office windows this spring. An internal employee stated that the company discussed the possibility of being spied on in meetings, with the final conclusion being that given Kalshi's past behavior style, such espionage and surveillance are completely plausible.

When asked about the espionage accusations, a Paradigm spokesperson responded that such claims are ridiculous. Kalshi spokesperson Jack Such responded that the relevant accusations are baseless and nearly delusional, and if Polymarket is willing to spend energy on self-examination, let it be; Kalshi will continue to diligently refine its products.

Kalshi co-founder Tarek Mansour spoke at the Semafor World Economic Summit in Washington, D.C. on April 15

Polymarket's investigation focuses on two points: how Kalshi precisely learned of its new product launch and marketing schedule in advance and what details it obtained in order to efficiently replicate everything.

Over the past year, suspicions within the platform have been continually accumulating, and an incident at an offline event in February became the catalyst for conflict. Polymarket had been preparing a community supermarket event since last November, set to open on February 12 in Manhattan: the first 300 customers to arrive would receive free fresh produce, for which it signed contracts totaling $643,380 for venue, brand setup, and execution.

Just 9 days before Polymarket's opening, Kalshi suddenly launched a free fresh produce marketing event at a Westside supermarket in New York, distributing $50 fresh voucher coupons and promoting it under the slogan "free market," while also launching predictions related to whether egg prices would rise or fall monthly.

Polymarket insiders stated that the other side clearly intended to divert traffic from their event. Founder Shayne, who grew up in New York, found this event particularly significant for the company, and the malicious interception left the team very disappointed.

Kalshi's public relations director Elisabeth Diana denied plagiarism, stating that their own fresh marketing plan had been in preparation for a long time and that they did not obtain the competitor's activity schedule through insider information; Kalshi spokesperson Such added that both activities were inspired by the mayor of New York City's promotion of fresh produce subsidy policies in his campaign.

Additionally, Polymarket has been secretly researching a real-time perpetual contract trading tool since this January, allowing users to bet on the rise and fall of stocks and other assets without holding positions, originally set for official announcement on April 21. However, just one hour before Polymarket's announcement, the tech media outlet The Information published an exclusive report citing anonymous sources, revealing that Kalshi was about to launch a similar perpetual contract product.

Polymarket's office is located in a fashionable area of New York, directly across from Paradigm

According to insiders, Polymarket's executives are very angry about this.

One insider stated, "They seem to know we are going to announce the news that day, which is very suspicious."

Such explained that Kalshi's perpetual product started development in 2024, and he believes The Information learned about this plan from a social media teaser released by Kalshi on April 13 on X. The teaser showcased a video that appeared to feature a spring toy in an infinite loop, accompanied by the text "Timeless," which in the financial field refers to perpetual futures contracts, meaning contracts that do not expire.

Polymarket's "Plagiarism File" contains more than a dozen pairs of official announcement documents, social dynamics, and product interface screenshots, with executives stating that these archived cases are only one-tenth of all similar incidents.

One page of the file records: On June 10, 2025, at 9:01 AM, Polymarket announced an hourly-level encrypted rise-and-fall prediction product on X, garnering nearly 24 million exposures; at 9:00 AM on the same day, the brokerage Webull and Kalshi jointly announced the launch of an identical product. Polymarket's document notes: "Same day?!"

But Such countered that Kalshi had already launched similar products before June 10, 2025, and that day was merely when Webull cooperated to list, rather, Polymarket's launch time was later, making it clear who copied whom.

There are also several cases of collided advertising materials. On Friday, August 22 last year, Polymarket ran ads for football betting in California on Meta, with prominent large text saying "Hey, California"; just a weekend later, Kalshi launched almost identical targeted ads with the same title.

Such stated that "Hey, California" is a common promotional phrase that is not protected by trademark copyright, and that determining commercial theft based solely on an advertising phrase is illogical.

The rivalry between the two prediction platforms continues to escalate in 2026. U.S. lawmakers and regulatory agencies are tightening regulations on prediction markets, with the industry suffering from criticism regarding insider trading and war betting; meanwhile, capital continues to make significant bets on both leading platforms.

According to data from the analysis company PitchBook, Polymarket has raised approximately $2 billion since its founding in 2020, with a targeted valuation of $15 billion in a new round of funding negotiations; Kalshi, founded in 2018, has raised a total of $2.6 billion, with the latest valuation doubling from last December to $22 billion.