The United Kingdom’s Financial Conduct Authority (FCA) has added crypto exchange Poloniex to its warning list of non-authorized companies. The Seychelles-based exchange is one of the three companies owned by or affiliated with entrepreneur Justin Sun that have suffered four hacks in the last two months.

The warning to Poloniex was published on the FCA’s website on Dec. 6. It doesn’t offer a reason but says that “firms and individuals cannot promote financial services in the UK without the necessary authorization or approval.” The FCA also reminds the public that it can’t count on financial law protection while dealing with unauthorized entities.

In August, the FCA revealed that since 2020, it has received 291 applications from crypto companies seeking registration and has approved only 38. In October, it announced that 140 crypto companies, including HTX and KuCoin, had been included on its warning list. Since then, the regulator has authorized only one entity, PayPal UK.

Cointelegraph reached out to Poloniex for comment but has not received a response.

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Poloniex became the victim of a $100-million hack on Nov. 10. According to the company, the platform has since “mostly completed” its restoration efforts and, by the end of November, was preparing to resume withdrawals and deposits.

On Dec. 5, the company resumed deposit and withdrawal services for specific cryptocurrencies via the Tron network, including Tether (USDT), USDD (USDD), BitTorrent (BTT), WINkLink (WIN), ApeNFT (NFT), Sun Token (SUN), Just (JST), Just Stablecoin (USDJ) and USD Coin (USDC). According to its official statement, “the resumption of deposit and withdrawal services for more cryptocurrencies on the platform will be implemented gradually.”

Tron founder Justin Sun also owns HTX, a crypto exchange formerly known as Huobi. Sun-linked platforms have suffered four hacks in the last two months. HTX lost $8 million in September’s attack and $30 million due to a hot wallet breach in late November.

At the same time, HTX’s HECO Chain bridge, a tool designed for moving digital assets between HTX and other networks like Ethereum, was also compromised by hackers, sending at least $86.6 million to suspicious addresses.

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