The Brent oil field lies beneath the North Sea, roughly one hundred and eighty-six kilometres north-east of the Shetland Islands. It was discovered in 1971, came onstream in 1976, and reached peak production of roughly half a million barrels per day in the early 1980s. It is now a mature, declining field producing a fraction of its historical peak. The platform that gives the benchmark its name is largely irrelevant to the global price of oil. What matters is not the physical Brent field but the financial architecture that was built around it over decades of trading, and which now anchors the pricing of roughly two thirds of the world's internationally traded crude.

This is the first important thing to understand about the oil benchmark system: the connection between the physical commodity and the financial price is more tenuous than most people assume. The price of Brent crude is not set by the volume of crude flowing from the Brent field. It is set by the trading of futures contracts on the Intercontinental Exchange in London, by the assessment of physical cargo prices by the price reporting agency Platts in its daily market-on-close process, and by the interactions between a global network of traders, producers, refiners and financial institutions who use the Brent price as a reference point for contracts governing hundreds of millions of barrels of crude that have nothing to do with the North Sea.

The physical Brent benchmark has evolved considerably since it was first established. The original Brent crude is now blended with crude from several other North Sea fields, including Forties, Oseberg, Ekofisk and Troll, to create what is formally known as BFOET crude. This blending was necessary because the production of physical North Sea crude has declined to the point where a benchmark based on a single field would be too easily manipulated by the small number of producers with the ability to affect supply. The addition of other streams has increased the liquidity of the physical market and made manipulation more difficult, though not impossible.

The price of Brent is established through a layered process. At the base is the physical spot market, where actual cargoes of North Sea crude change hands through negotiated transactions between producers, traders and refiners. These physical transactions are reported to and assessed by price reporting agencies, principally S&P Global Commodity Insights, operating through its Platts brand. Platts publishes daily assessed prices for a range of crude grades based on its monitoring of the physical market, and those assessed prices form the basis for many long-term supply contracts between producers and refiners.

Above the physical market sits the futures market on the Intercontinental Exchange. The Brent futures contract allows buyers and sellers to agree today on a price for the delivery of crude at a specified future date, most commonly one to three months forward. The futures market is enormously larger than the physical market in terms of volume traded: the number of futures contracts traded on any given day represents many times the actual volume of physical crude that changes hands. Most futures contracts are settled financially rather than through physical delivery, meaning that the buyer and seller exchange cash based on the difference between the agreed price and the settlement price, without any crude actually moving.

West Texas Intermediate is the second major global oil benchmark. It is a light, sweet crude produced primarily in the Permian Basin of West Texas and New Mexico, one of the most productive oil-producing regions in the world and the heart of the shale revolution that transformed the United States into the world's largest crude producer by 2018. WTI is physically delivered at Cushing, Oklahoma, a landlocked storage and pipeline hub that connects producing regions in the south and west of the United States to refineries concentrated on the Gulf Coast.

The landlocked nature of the Cushing delivery point has historically been the defining characteristic of the WTI benchmark and the source of its most notable dysfunction. Because WTI can only leave Cushing by pipeline, its price is sensitive to the storage capacity at Cushing and the pipeline connections available to move crude away from the hub. When those pipelines are constrained and storage approaches capacity, WTI can trade at a significant discount to Brent that reflects the difficulty of getting the crude to where it is actually needed rather than any fundamental difference in quality. The most extreme expression of this dynamic occurred in April 2020, when WTI futures briefly traded at negative forty dollars per barrel as the collapse in demand caused by the pandemic coincided with storage at Cushing approaching its physical limits and holders of futures contracts desperate to avoid taking physical delivery of crude they had nowhere to put.

The infrastructure constraints that historically made WTI a primarily domestic benchmark have been progressively resolved by the expansion of pipeline capacity to the Gulf Coast and the lifting of the United States crude export ban in December 2015. American crude now trades in global markets, and WTI has become an increasingly important reference price for Atlantic Basin crude in competition with Brent. The Brent-WTI spread remains actively traded, and its movements reflect changes in the relative supply and demand conditions in the Atlantic Basin versus the American domestic market, pipeline constraints, shipping costs and a range of other factors that create opportunities for arbitrage between the two benchmarks.

The third major benchmark, less frequently cited in Western financial media but critically important for global oil pricing, is Dubai crude. Dubai is a medium, sour crude produced in the United Arab Emirates and traded primarily as a reference for crude flowing to Asian refineries. The Dubai benchmark is the primary reference price for Gulf crude exported to China, Japan, South Korea and the other major Asian importers, and it anchors the pricing of a significant portion of OPEC production that is sold into Asia under long-term supply contracts.

The relationship between Brent and Dubai is expressed through a differential known as the EFS, or Exchange of Futures for Swaps, which reflects the premium that light, sweet crude commands over medium, sour crude. When the EFS widens, it signals that the Atlantic Basin market is tighter relative to the Asian market, creating incentives for crude to be redirected from east to west. When it narrows, the incentive runs in the opposite direction. The EFS is therefore one of the key signals that orchestrates the global flow of crude between regions, and its movements are watched closely by the trading desks of the major commodity houses whose business is precisely to exploit the differentials between markets.

Between the physical market and the futures market sits a set of institutions whose power over global oil pricing is inversely proportional to their public profile. Price reporting agencies, principally S&P Global Commodity Insights operating through Platts and Argus Media, assess the prices of physical crude and product markets on a daily basis and publish those assessments in publications that are used as the basis for contracts covering an enormous volume of global trade.

The assessed price produced by a price reporting agency is not a market price in the conventional sense. It is a judgement made by a small team of analysts about what the fair value of a particular grade of crude is at a particular moment, based on the transactions and bids and offers they have observed in the market during the assessment window. This judgement is enormously influential: the Platts Dated Brent assessment, published daily, is the reference price for contracts covering several billion dollars of crude transactions every day. The methodology used to produce it, the trades included in or excluded from the assessment, and the judgements made about the representativeness of particular transactions are therefore matters of considerable commercial significance.

The concentration of pricing power in a small number of private agencies has attracted criticism and regulatory scrutiny, particularly after the LIBOR scandal demonstrated how benchmark manipulation could be sustained over long periods and at enormous cost to market participants who had no means of independently verifying the accuracy of the benchmarks they relied on. Oil benchmark manipulation has been alleged on several occasions, and the structure of the physical oil market, with its limited transparency and its reliance on the assessments of private agencies, creates conditions that make manipulation difficult to detect and even more difficult to prosecute.

For the vast majority of countries and consumers, the benchmark system is an invisible architecture that determines the price of an essential commodity without their knowledge or participation. The government of Mauritius does not negotiate the price of the petroleum products it imports by reference to any assessment it makes of the underlying value of crude oil. It pays a price that is derived from the Brent benchmark, adjusted for the quality and grade of the product, the freight cost from the loading port to Port Louis, and the insurance and other charges attached to the shipment. The Brent price, set in London by the interaction of a futures market and a physical assessment process, is the foundational input into every element of Mauritius's fuel import cost.

This is true of every oil-importing economy that lacks the market power to negotiate prices outside the benchmark system. The benchmark is not neutral. It reflects the interests and operations of the market participants who are most active in shaping it: the large trading houses, the major producing companies, the financial institutions with significant positions in the futures market. It does not reflect the interests of the small importer who has no futures market exposure, no physical trading desk and no ability to arbitrage between grades or delivery points. For that importer, the benchmark is simply the price. It is given, not negotiated. It arrives from outside, and the only question is how much of it can be absorbed before the domestic social and fiscal consequences become politically unsustainable.

Understanding the benchmark system does not give the small importing economy any additional leverage over its energy costs. But it clarifies where the leverage is not, and why efforts to manage import costs through domestic policy alone will always be operating within constraints set by a global pricing architecture that was not designed with small economies in mind and cannot be reformed by them acting alone.