In the early weeks of war, one of the Persian Gulf’s most critical maritime arteries quietly became the stage for an extraordinary experiment in modern energy logistics. Just weeks into the conflict, the United Arab Emirates began moving crude oil out of the Strait of Hormuz using methods more commonly associated with sanctioned states. Ships sailed without their transponders switched on, often under cover of darkness, before transferring cargo to waiting tankers outside the waterway. The operation, later described through vessel tracking data compiled by Bloomberg and corroborated by analytics firms including Vortexa and Kpler, marked a shift in how one of the world’s top oil producers adapted to wartime risk.
At the center of this evolving system was the urgent need for capacity. Abu Dhabi required enough vessels to repeatedly carry crude through one of the world’s most dangerous chokepoints, not once but continuously. That demand led to an unexpected figure emerging as a key player: South Korean shipping tycoon Ga-Hyun Chung and his Sinokor Group.
Sinokor, traditionally a smaller participant in the oil tanker sector, had already been expanding aggressively before the conflict. But as tanker markets surged to historic profitability levels during the disruption, the company accelerated its expansion into supertankers at unprecedented speed. Bloomberg reporting in March noted that Sinokor stood to benefit significantly from volatility in oil trade flows, as shipping rates climbed sharply across global routes.
By mid-April, Sinokor had begun leasing vessels to Abu Dhabi National Oil Company’s shipping arm, Adnoc L&S, for repeated “shuttle runs” through the Gulf. These voyages involved loading crude at UAE terminals, sailing covertly through the Strait of Hormuz into the Gulf of Oman, and transferring cargo to other ships waiting outside the strait before returning for new loads. According to ship tracking data cited by Bloomberg and compiled by Vortexa, by June nearly half of Emirati crude shipments were moving on vessels controlled by Sinokor.
The scale of the operation was significant not only for its logistical complexity but also for its financial implications. Shipbrokers estimated that even a small number of vessels conducting these “dark transits” could generate between 60 million and 120 million dollars in earnings over a few months, with rates during the conflict reaching as much as three to four times pre-war levels. Sinokor’s expanding presence placed it among the most influential participants in a tanker market widely described as one of the most lucrative in history.
The mechanics of the operation relied on a carefully coordinated system of movement and timing. Tankers departed UAE ports such as Zirku and Das Island, often with transponders switched off as they entered the Persian Gulf. They moved in coordinated convoys along the Omani coastline before rendezvousing in the Gulf of Oman with empty vessels positioned to receive crude. From there, cargoes were transported onward to global markets. Without active tracking signals, analysts were left relying on satellite imagery and commercial datasets to reconstruct movements through one of the world’s most sensitive maritime corridors.
While Adnoc also deployed its own fleet and vessels from other operators, including firms such as Navig8, the partnership with Sinokor proved central to scaling exports rapidly. This expansion allowed the UAE to return to near pre-war export levels faster than regional competitors and to capitalize on elevated oil prices during the conflict period.
Bloomberg reporting, drawing on vessel tracking data and industry sources, also highlighted how Sinokor’s rise was tied to a broader restructuring of the tanker market. The company’s rapid acquisition and chartering of very large crude carriers gave it control over a significant portion of available global capacity. By late February, industry estimates suggested Sinokor controlled around 150 VLCCs, representing a substantial share of the non-sanctioned global fleet.
As the war intensified and shipping risks increased, traditional patterns of oil movement across the Strait of Hormuz began to shift. Some operators diverted cargoes to alternative export routes via pipelines to the Gulf of Oman and the Red Sea, while others attempted limited transits through the strait. Early in the conflict, ships linked to Iran were among the most visible users of the corridor, but by mid-war a wider range of commercial operators had adopted similar “dark” or semi-covert navigation strategies.
Industry participants described the emergence of what some referred to informally as “milk runs,” with repeated shuttle movements replacing traditional long-haul voyages. Sinokor’s role in these operations expanded further as it began controlling a growing share of vessels available for immediate deployment into the Gulf. At points during the period, the company was estimated to control nearly all supertankers capable of reaching the US Gulf within a 30-day window.
The financial incentives for such positioning were reinforced by extreme volatility in freight markets. Rates surged as a large portion of global capacity became constrained within or near the Persian Gulf, while demand for oil transport remained elevated. Sinokor’s strategy of positioning empty tankers in advance of loading opportunities further amplified its advantage during the disruption.
As operations expanded, the scale of crude movement through the Strait of Hormuz became increasingly difficult to measure precisely. Estimates during early June ranged widely, with some analysts suggesting flows of around two million barrels per day, while others, including major financial institutions, placed the figure significantly higher. US Energy Secretary comments at the time suggested volumes could reach as high as seven million barrels per day, underscoring the uncertainty created by limited visibility into maritime movements.
Despite the risks associated with operating in a conflict environment, Sinokor continued to expand its presence. Shipbroker communications cited in Bloomberg reporting indicated that the company was actively marketing its fleet for additional cargoes, including routes from Iraq and other Gulf exporters. In late June, Sinokor reportedly informed brokers of provisional bookings at some of the highest freight rates recorded during the year, reflecting sustained demand for capacity even as market conditions began to stabilize following a temporary ceasefire.
The interim peace agreement between the United States and Iran eventually led to a partial normalization of shipping flows through the Strait of Hormuz, with some vessels resuming standard transponder use and navigation patterns. However, the legacy of the “dark transit” period persisted in the form of expanded operational networks, increased fleet deployment, and heightened awareness of alternative routing strategies across the industry.
Even as rates began to moderate, Sinokor remained heavily involved in Gulf operations. Industry estimates suggested the company controlled more than a third of VLCCs capable of immediate deployment into the region, maintaining a strong position in a market still adjusting to post-conflict conditions. By late June, reports indicated that at least 18 supertankers had been dispatched into the Gulf in a single week under Sinokor control, highlighting the scale of its continued engagement.
In messages circulated to shipbrokers, the company emphasized its readiness to transit the Strait of Hormuz after loading, reflecting renewed confidence in access to the waterway. These communications, alongside vessel tracking data and broker estimates, reinforced Sinokor’s role as one of the most influential actors in a rapidly evolving tanker market.
As Bloomberg’s reporting and associated maritime data sources illustrate, the convergence of war, market disruption, and aggressive fleet expansion created an environment in which a relatively private shipping group was able to exert outsized influence over global crude flows. The Strait of Hormuz, long recognized as a critical chokepoint for global energy supply, became not only a theater of geopolitical tension but also a testing ground for new forms of maritime logistics driven by risk, profit, and rapid adaptation.
In the aftermath, as oil markets adjust to shifting supply routes and renewed shipping activity, the events surrounding the Hormuz shuttle operations continue to shape freight strategies, vessel deployment, and the balance of power within the global tanker industry.
