Start with the numbers. Reuters' Singapore spot close for 30 October 2026: naphtha CFR Japan M1 (first-half December) at $1,115.50/mt, up $30.00 on the day and a six-month high; M2 (second-half December) at $1,068.25/mt, up $30.25; the M1/M2 backwardation at $47.25/mt. On the same table the naphtha-Brent crack widened to $237.18/mt (+$8.92) and the naphtha netback FOB Singapore printed $121.94/bbl (+$3.33). On 28 October, just two sessions earlier, afternoon indications for CFR Japan naphtha were still $1,053.50/mt, below the previous close of $1,059.25 — the front-month cargo was repriced roughly $56 higher within two trading days, while the backwardation held at a steep $47-plus throughout.

There are two layers to the move. The surface one is geopolitics: Reuters reported on 30 October that a fresh tanker attack in the Strait of Hormuz reignited supply concerns, with crude benchmarks rising in tandem and naphtha following. The deeper one is Japanese buying: in tenders the same day, Japanese buyer AMEC took both first- and second-half December cargoes at high premiums, effectively setting the price signal for the front month. Supply is tighter still. QatarEnergy's 28 October spot tender offered only 55,000 mt, loading free-on-board from Ras Laffan — a port inside the Strait of Hormuz — between 3 and 5 November, so the load port itself sits inside the risk zone. At the same time, persistently high freight has cut Western arbitrage arrivals into Asia in November, leaving regional naphtha supply on the tight side.

The divergence is the part worth recording. On the same day the gasoline crack collapsed from $21.70 to $10.53/bbl, down $11.17 in a single session and the lowest since 2 March, with 92-RON gasoline at $127.64/bbl (-$8.36), 95-RON at $128.14 and 97-RON at $129.20. The drivers were a broad-based slide in global cracks together with China's rare fourth batch of fuel export quotas. Two arrows now point in opposite directions: naphtha is strengthening against crude ($237.18, +$8.92) while gasoline is weakening against it ($10.53, -$11.17). For refiners, processing economics are shifting from a product-driven to a petrochemical-feedstock-driven logic: making more naphtha and chemical light ends and less finished fuel is the more profitable configuration right now. The ethylene leg has not deteriorated in parallel — CFR Northeast Asia ethylene was assessed at $1,210/mt on 28 October (+$10), still at the top of the $1,200-plus tradable range, which tells us the cracker margin has not yet been fully eaten by feedstock.

What this means for SNSUC. Naphtha is a hazardous chemical and falls outside our trading scope, but this divergence transmits directly into the categories we do touch. Base oils and naphtha run through different units, yet they share the same refinery processing decision: when diesel and naphtha premiums over crude widen, refiners shift feedstocks such as vacuum gasoil toward fuel and petrochemical streams, and base oil output gives way passively. Japan's August data already confirms it — asphalt output rose to a five-month high and outpaced base oils for the first time in five months, while Asian Group I and Group II prices weakened relative to diesel, giving refiners every reason to prioritise diesel over base oils. Strength at the feedstock end therefore tightens base oil supply, which supports rather than undermines SN150/SN500 offers. Operationally, our base oil quotes to Japan and the wider East Asian market should carry shorter validity windows, lock grade and batch explicitly, and leave buffer for arrival timing through the fourth-quarter maintenance season. Risk note: this is a market observation based on public data and does not constitute investment advice.