UNUS SED LEO (LEO) is the utility token at the heart of the iFinex ecosystem, the company behind the cryptocurrency exchange Bitfinex. Launched in 2019, LEO aims to both increase platform loyalty and create a value cycle within the ecosystem by offering Bitfinex users various advantages. The name derives from the Latin phrase "unus sed leo," meaning "one, but lion (alone, but powerful). In this guide, we will examine the LEO token's functions, how it emerged, its history, technical structure, use cases, and future prospects step by step.Definition and Origins of UNUS SED LEOUNUS SED LEO (LEO for short) is a utility token developed by iFinex for use on the Bitfinex exchange and related products. LEO token holders benefit from various privileges on the Bitfinex platform, including transaction fee discounts, easy withdrawal/deposit options, and advantages in lending (borrowing/lending) transactions. The primary purpose of this token is to increase user loyalty to iFinex products and create a value capture mechanism by linking platform revenues to the token's value.The LEO token was introduced in May 2019 and quickly launched through a private sale. Bitfinex managed to raise $1 billion in just 10 days through this private sale in May 2019. The token sale was held at a fixed price of 1 LEO = 1 USDT, and all tokens were sold to private investors. LEO quickly became a core asset of the Bitfinex ecosystem.The LEO token was developed by iFinex Inc., Bitfinex's parent company. The global fintech team at iFinex implemented LEO with an infrastructure focused on security and scalability. Paolo Ardoino, CTO of Bitfinex and Tether, led the project's technical leadership. Ardoino and his team aimed to improve the user experience by integrating the LEO token into iFinex's existing systems.The LEO token's creation stemmed from Bitfinex's goal of addressing a financial gap in its ecosystem and creating long-term value. In 2018, governments froze approximately $850 million in funds entrusted to Bitfinex's payment processor, Crypto Capital, leaving the company in a difficult position. To address this shortfall and rebuild user trust, iFinex launched a LEO token sale in 2019, raising approximately $1 billion. The funds raised were used to meet Bitfinex's financial obligations and maintain its operations. Furthermore, LEO was designed not only as a crisis resolution tool but also as a long-term value storage tool within the iFinex ecosystem. iFinex aimed to support the token's value and increase user loyalty by sharing a portion of its platform revenues with the community through LEO.The LEO token is one of the few projects that technically stands out with its dual-chain structure. Since its inception, LEO tokens have been issued on two different blockchains: approximately 66% on the Ethereum network using the ERC-20 standard (660 million tokens) and 34% on the EOS network using the EOSIO protocol (340 million tokens), totaling 1 billion tokens. LEO tokens from both networks are fungible on the Bitfinex platform, giving users the flexibility to simultaneously access Ethereum's extensive DeFi ecosystem and benefit from EOS's low transaction fees. The dual-chain structure provides LEO with cross-platform compatibility and ease of liquidity.While the LEO token has various uses primarily within the Bitfinex exchange, it was designed as a utility asset that extends throughout the iFinex ecosystem. The primary uses for LEO are as follows:Trading fee reductions on Bitfinex: LEO token holders pay lower transaction fees for crypto-to-crypto trades on the Bitfinex exchange. A 15% discount on taker fees, particularly across all cryptocurrency trading pairs, is a key advantage of holding LEO. Additional fee reductions are also available for users holding large amounts of LEO (such as an additional 10% discount for balances above certain thresholds). These discounts provide a significant cost advantage for traders who engage in intensive trading.Lower costs for Lending and Borrowing: In Bitfinex's P2P lending market, the LEO token offers benefits for both lenders and borrowers. Lenders receive a 0.05% discount on commissions for every 10,000 LEO they hold, depending on the amount of LEO they hold, and this discount can reach up to 5% in total. This allows users holding LEO to earn higher net returns on their lending transactions. Borrowers have the opportunity to use LEO tokens as collateral. On the Bitfinex Borrow platform, users can borrow USDT or other assets using LEO as collateral, thus using LEO in their portfolios as a financing tool.Payments with Bitfinex Pay: Bitfinex Pay is a payment gateway that allows online businesses to accept payments with cryptocurrency. In this system, the LEO token can be used as a fast and low-cost payment tool. When an e-commerce site integrates Bitfinex Pay, customers pay low transaction fees by making payments with LEO tokens. Payments made with LEO can also be converted to a fixed asset like USDT, thanks to Bitfinex's instant conversion feature. New token sales and launchpad privileges: iFinex announced LEO in 2019, simultaneously introducing its own IEO platform, Tokinex. On this platform, similar to Bitfinex Launchpad, LEO is positioned as a native utility token. LEO token holders can gain privileges such as early access to new project token sales (IEOs) organized by iFinex or Bitfinex, or guaranteed allotments. For example, users who hold a certain amount of LEO at a launchpad event can pre-emptively guarantee the right to purchase a certain percentage of the newly released token. This adds additional utility to LEO, giving token holders priority access to investment opportunities.VIP status and special programs: Bitfinex offers various VIP programs to customers who trade high volumes on its exchange or hold substantial assets. The LEO token is one factor influencing these VIP levels. Users who hold a significant amount of LEO can earn VIP user status on Bitfinex. VIP users; They receive privileges such as higher withdrawal limits, dedicated customer representative support, reduced transaction fees, and invitations to special events. For example, a user holding more than 50 million LEO tokens can be exempt from monthly fiat withdrawal fees up to $2 million, and the additional fee for withdrawals above this limit will be reduced to 2% instead of 3%.The History of UNUS SED LEO: Key MilestonesThe story of UNUS SED LEO began with a strategic move taken by Bitfinex in 2019 to overcome the challenging financial period it experienced. Born as the iFinex ecosystem's recovery plan, the LEO token quickly became central to Bitfinex's long-term growth model. Let's take a look at LEO's journey from its launch in 2019 to its all-time high in 2025:2019: LEO Launch: iFinex, the parent company of Bitfinex and Tether, launched the UNUS SED LEO token in May 2019. A private token sale raised 1 billion USDT, and the tokens were completely sold within 10 days. That same year, Bitfinex introduced its token burn mechanism in its whitepaper. iFinex announced that it would purchase and burn LEO from the market with a portion of its platform revenues.2020: EOS integration: The EOS-based version of the LEO token became widely used during this period. Bitfinex integrated LEO support on the EOS network, in addition to Ethereum, allowing users to make faster and cheaper LEO transfers. With the full implementation of the dual-chain infrastructure, LEO holders were able to transfer their tokens between the Ethereum and EOS networks through Bitfinex.2021: Ecosystem expansion: This year, Bitfinex diversified its platform by launching new products and services such as Bitfinex Pay and Bitfinex Borrow. The LEO token's usability has also expanded with these innovations. For example, with the launch of Bitfinex Pay in March 2021, online stores began accepting LEO as a payment instrument. Similarly, on the Bitfinex Borrow lending platform, LEO has been integrated into P2P borrowing/lending transactions, becoming part of users' collateral portfolios and offering discounted rates. iFinex announced plans to offer similar benefits to LEO token holders across all new products and platforms it launches in the future. This strategy began to be implemented in 2021.2022: Wider adoption and integration: 2022 marked the beginning of the LEO token's rise to prominence outside the iFinex ecosystem. Integrations with Bitfinex's sister company, Tether, deepened, and LEO became widely adopted as a payment instrument across various platforms. Online businesses that integrated Bitfinex Pay accepted payments in LEO, offering their users an alternative cryptocurrency payment option. iFinex also began considering LEO as a potential utility asset in its new subsidiary ventures, such as Bitfinex Securities.2023-2024: Regular burns and supply reductions: During this period, iFinex continued its promised transparent burn program for the LEO token. Monthly burn reports continued to be published on Bitfinex's real-time LEO Transparency Dashboard, and on-chain burns, occurring every three hours, continued to be shared with the community. By the end of 2024, a significant portion of the total LEO supply had been burned out of circulation; tens of millions of the approximately 1 billion tokens released were permanently destroyed. For example, approximately 51 million LEO tokens had been burned by mid-2021.2025: New High (ATH) and Market Performance: In line with the general recovery trend of the crypto market, the LEO price gradually rose throughout 2024, reaching an all-time high in March 2025. On March 3, 2025, the LEO price broke its own record, reaching approximately $10.01. This level surpassed the previous peak of $8.14 in February 2022 and pushed LEO's market capitalization to over $9 billion. By 2025, LEO had taken the top spot among the largest centralized exchange tokens.Why is UNUS SED LEO Important?So, why is UNUS SED LEO such an important cryptocurrency? The coin's mechanism and ecosystem contain many elements that add value to crypto. We can examine them under the following headings:Deflationary Economic ModelThe most striking feature of the LEO token is its deflationary supply structure. Bitfinex and its affiliates purchase LEO tokens from the market with at least 27% of their consolidated monthly revenue and burn them. This regular buyback and burn mechanism aims to support the token's value by reducing the total supply over time. Since the scarcity of available tokens increases as the supply decreases, the theoretical aim is to exert positive pressure on LEO's market price.Advantages in the Bitfinex ecosystemLEO offers tangible benefits for users actively trading on the Bitfinex platform. For example, users who hold LEO can receive up to a 15% discount on trading fees paid on the exchange. Furthermore, LEO holders receive up to a 5% commission discount in Bitfinex's peer-to-peer lending market (P2P lending). Those using LEO collateral on the Bitfinex Borrow service can benefit from lower interest rates. In integrated payments with Bitfinex Pay, LEO also stands out as a tool that minimizes transaction fees and enables fast transfers.LEO TransparencyiFinex has created a "LEO Transparency Dashboard" to ensure full transparency of its LEO token burn program. All LEO amounts burned through this platform and the corresponding transaction IDs are shared in real time. This allows community members to verify on the blockchain that the company's promised buybacks and burns are being carried out regularly.Dual-chain structure and broad ecosystemLEO's ability to operate on both the Ethereum and EOS networks offers technical flexibility and cost advantages to its users. LEO tokens on Ethereum enjoy broad exchange and wallet support, while LEO tokens on EOS offer advantages such as low transaction fees and fast confirmation times. This dual-chain structure allows users to choose the most suitable network for LEO transfers based on market conditions. For example, during periods of congestion on the Ethereum network and higher fees, it is possible to transfer LEO over the EOS network at a much lower cost.Furthermore, the LEO token creates a value link between the iFinex group's various products and services, enabling ecosystem integration. The Bitfinex exchange, the Tether (USDT) stablecoin, Ethfinex/DeversiFi, and other iFinex initiatives are indirectly linked to LEO. For example, LEO could potentially play a role in new projects launched by iFinex, or some revenue from Tether transactions could be channeled towards LEO burning. In this sense, LEO is seen as a token that internally fuels the value cycle within the iFinex ecosystem. Because users gain advantages across all platforms of the iFinex family by holding LEO, they become more connected to the ecosystem.LEO Token EconomyWhen considering the value of LEO, it is necessary to consider its token economy. The cryptocurrency's characteristics can be summarized as follows:Total Supply: A total of 1 billion LEO tokens were initially created. Approximately 66% of this supply was issued on Ethereum, and 34% on the EOS network. After the initial distribution, no new LEO tokens were minted.Circulating Supply: Due to regular burns, the circulating supply of LEO is constantly decreasing. The circulating supply, which was 1 billion in 2019, decreased to approximately 923 million LEO by October 2025. The remaining supply was burned by iFinex and completely removed from circulation.Standard: It utilizes the ERC-20 (Ethereum) and EOSIO (EOS) token standards. This means LEO exists as an ERC-20 token on the Ethereum blockchain and as an EOS token on the EOS blockchain. On the Bitfinex platform, users can instantly convert LEO tokens between the two networks.Burning Mechanism: At the heart of LEO tokenomics is the buyback and burn mechanism. As stated in its whitepaper, iFinex pledged to purchase and burn LEO tokens from the market with at least 27% of its consolidated gross revenues each month. This process will continue until there are no tokens left in the market. Furthermore, Bitfinex pledged to accelerate the LEO burn once it recovers from exceptional financial losses in the past. For example, if any portion of the frozen Crypto Capital funds or the assets stolen in the Bitfinex hack are recovered, iFinex announced that it will use 80% of this amount to buy and burn LEO from the market. All burn transactions are executed via smart contracts and are verifiable on the blockchain.UNUS SED LEO Developers and CommunityAs previously mentioned, the LEO token is a centralized cryptocurrency developed by iFinex Inc. iFinex is a global fintech company that operates the Bitfinex exchange and Tether. The company's development team consists of experienced professionals in finance and software. Paolo Ardoino, Bitfinex's technical leader, played a key role in the LEO project's development. As CTO (Chief Technology Officer) of Bitfinex and Tether, Paolo Ardoino led the team that planned and implemented the LEO token's infrastructure. The team's primary goal was to seamlessly integrate LEO into the Bitfinex platform and ensure the token's reliability.The LEO token community largely consists of Bitfinex users and crypto investors who hold the token for the long term. Traders actively trading on the Bitfinex exchange hold the token in their portfolios to take advantage of the discounts and advantages offered by LEO. DeFi investors and long-term supporters of the iFinex ecosystem are also part of the LEO community. Because LEO was initially designed as a centralized token, project management is entirely under iFinex's control. However, thanks to iFinex's transparent burn policy and regular disclosures, we can say that there is a trust-based relationship between the community and the company. For example, iFinex continues to clearly disclose the amount of its revenue allocated to LEO purchases and burns each month.Furthermore, to support the LEO token economy, iFinex keeps the ecosystem vibrant by consistently allocating a portion of its revenue to token buybacks. This model aligns the interests of the company and token holders. As Bitfinex revenue increases, more LEO is burned, increasing the potential for LEO held by existing token holders to appreciate.Frequently Asked Questions (FAQ)Below are some frequently asked questions and answers about UNUS SED LEO:What is UNUS SED LEO and when was it released?: UNUS SED LEO is a utility cryptocurrency token launched in 2019 by iFinex, the parent company of the Bitfinex exchange. It was issued to offer various on-platform benefits to Bitfinex users and was initially launched in May 2019, raising $1 billion in a private sale.Who developed LEO?: The LEO token was developed by iFinex Inc. The team behind the project is a global fintech team that also manages the Bitfinex exchange. Paolo Ardoino (CTO of Bitfinex and Tether) led the technical development of LEO, and the engineering team under his leadership successfully integrated the token into the Bitfinex ecosystem. Which blockchains does LEO exist on?: The LEO token has a dual-chain structure and exists on two separate blockchains: Ethereum and EOS. While it operates as an ERC-20 token on the Ethereum network, equivalent LEO tokens exist on the EOSIO protocol. Users can easily convert their LEO between these two networks through Bitfinex. (Note: Bitfinex transitioned its EOS-based LEO tokens to its own sidechain called "Vaulta" in 2025, replacing EOS with this private network; however, the underlying functionality remains similar.)What is the LEO token used for?: LEO is primarily designed to benefit the Bitfinex ecosystem. Users who hold LEO receive discounts on transaction fees on Bitfinex, which is particularly important for high-volume traders. LEO also offers commission discounts on lending/borrowing transactions and the ability to be used as collateral. LEO can also be used as a payment instrument when making purchases through Bitfinex Pay, Bitfinex's crypto payment service. In summary, the LEO token, as an on-platform loyalty and utility token, provides users with financial advantages and easier access to additional services.How does LEO's burn mechanism work?: LEO's burn mechanism is based on iFinex's revenue sharing model. At the end of each month, the company repurchases LEO tokens from the market with 27% of the previous month's revenue and burns these tokens, removing them from circulation. This process is planned to continue until all LEO tokens are destroyed. For example, a determined share of Bitfinex's transaction fees, funding revenues, and other operating profits is automatically allocated to LEO purchases. Purchased LEO tokens are irrevocably burned from wallets at regular intervals during the relevant month (the burn process is publicly visible on the blockchain). This mechanism continuously reduces the LEO supply, aiming to support the token's value in the long term. Is LEO suitable for investment?: Since LEO is primarily a utility token, it is designed to benefit Bitfinex users rather than serve as a direct investment vehicle. Of course, LEO's value may increase over time (for example, it reached $10 in 2025, generating significant returns), but this increase is largely dependent on the success of the Bitfinex platform and iFinex's commitment to burning it. Compared to other exchange tokens like Binance's BNB, LEO has a more limited use case and relatively low daily trading volume. Therefore, LEO is more suited to users who believe in the Bitfinex ecosystem and want to establish a long-term relationship. As with any investment decision, investing in LEO requires evaluating one's own risk tolerance and expectations.To closely monitor the future of exchange tokens like LEO and the latest market developments, visit the JR Kripto Guide section.