Russia suspended diesel exports this summer while Ukrainian drones kept striking the refineries that would have supplied them, and the world's remaining fuel plants have been running flat out ever since. American refineries operated at 96.5% of capacity in late July, processing 17.2m barrels of crude a day, and distillate stocks still sat about 12% below their five-year seasonal average. The benchmark US 3-2-1 crack spread — the margin on turning three barrels of crude into two of gasoline and one of distillate — reached an all-time high near $72 a barrel, with diesel cracks above $91. It started the year near $20.

The quarter was real

Marathon Petroleum, which runs Gulf Coast, Mid-Continent and West Coast plants alongside a pipeline network feeding about 7,159 branded outlets, saw its refining and marketing margin double to $36.33 a barrel from $17.58. Net income was $5.14bn against $1.22bn.

Valero Energy, with 15 refineries totaling roughly 3.2m barrels a day plus ethanol and renewable diesel plants, took refining operating income to $4.5bn from $1.3bn and raised its dividend to $1.20. Phillips 66, which pairs 12 refineries with chemicals and midstream businesses, said it captured 98% of the market crack indicator and guided to a 95% capture rate this quarter. HF Sinclair, an independent refiner across six interior states now separating its lubricants arm into a standalone company, more than doubled refining EBITDA. Delek US, four refineries and 248 convenience stores, swung from a $106m loss to $169.5m of profit. PBF Energy, a merchant refiner with six plants and no upstream cushion, went from a 0.6% operating margin to 10.9%, though $250m of that came from an insurance settlement on its Martinez fire.

Management teams argue this is not a spike. Valero told investors roughly 5m barrels a day of global capacity is offline across the Middle East and Russia and product inventories sit about 130m barrels below normal, with no full recovery through 2027. Two US plants are gone for good: LyondellBasell's 263,776 b/d Houston refinery closed in early 2025, and Phillips 66 permanently stopped crude processing at Wilmington, California, 139,000 b/d.

The share moves, though, were not gradual. From mid-July to 7 August the six names were flat to slightly down, earnings and all. Then between 8 and 14 August they gained 15.3% on average, rising together on four consecutive sessions as the diesel crack exploded on the Russian export ban and renewed Hormuz tension. This was a commodity shock priced into equities, not a verdict on any one company.

What consensus already assumes

Every one of the six trades below its trailing multiple on forward earnings — Marathon at 7.75x against 12.2x trailing, PBF at 5.27x, Phillips 66 the dearest at 10.38x. That looks like a group priced for collapse. It is closer to the opposite. Analysts model Marathon's earnings per share falling from $45.87 this year to $30.77 in 2027 and $19.66 in 2028. On that last figure the stock sits at 18.1x, Valero at 17.5x, and Delek at a small loss. The cheap forward number is peak-cycle arithmetic; the out-year number is what the market is actually paying.

On assets the picture splits. PBF trades at 1.33x book and 4.77x trailing EBITDA, near tangible value, and cut net debt by $1.4bn in the quarter. HF Sinclair is at 1.63x book with a 15.3% free-cash-flow yield. Marathon is at 5.42x book and Delek at 9.5x — the two ends of the same trade.

There is a second split worth noting. Marathon, Valero, Phillips 66 and HF Sinclair have all shrunk their diluted share counts, Marathon by 5.8% in a year and from 638m in 2021 to 291m now. The two twelve-month leaders have gone the other way: PBF's count rose 5.6%, Delek's 3.3%. The stocks that ran hardest are the ones whose owners got diluted. Marathon, Phillips 66 and Valero returned $6.3bn in the quarter, and TD Cowen's Jason Gabelman estimates Valero and Marathon will buy back about 20% of their market value by end-2027 — while cutting his rating on Valero on the view that the refining outlook priced in is too bullish.

Two dated risks sit ahead. Delek said crude backwardation compressed from $6-7 to about $1.50, which feeds into third-quarter cracks roughly one-for-one, and that it carries no meaningful hedge on its spread. And global refinery downtime is projected near 8.5m barrels a day in October as autumn maintenance peaks — capacity offline that supports cracks but also means barrels these companies do not run.

The setup

Where it stands — Record diesel cracks delivered the best refining quarter since 2022, and five August sessions repriced all six names together.

Would confirm — Distillate inventories staying more than 10% below the five-year seasonal average through the autumn turnaround season.

Would invalidate — 2027 consensus earnings per share for Marathon holding near $30 rather than being cut toward the 2028 path.

Watch next — October, when global refinery downtime peaks near 8.5m barrels a day; third-quarter results follow in late October.

Valuation — Marathon at 12.2x trailing and 7.75x forward earnings, but 18.1x its own 2028 consensus; group forward range 5.3x-10.4x.