I. Three-Layer Pricing Framework

Layer 1 · OSP Table Discount. Per SOMO's Aug 10 notice (Reuters / Sina / Eastmoney), September-loading Basrah Medium is set at a -$4.00/bbl discount to the Oman/Dubai average (August -$6.50), and Heavy at -$7.30/bbl (August -$8.80). Both grades were raised as Iraq narrowed discounts under war risk premium.

Layer 2 · Spot Deduction (term cash rebate). The latest available real range is August Medium 25–29.80, Heavy 27.80–29.80 USD/bbl cash deduction (data being updated; subject to latest). This is the extra downside buyers actually capture.

Layer 3 · Loading Premium. The September tender loading premium is computed on FOB STS transfer: days 1–10 ≥$0.20, days 11–30 ≥$3.00 per barrel, plus a 30% surcharge on the STS portion. Later laycans carry higher premiums.

II. Net-to-Arrive Calculation

Using Sep 20 reference Oman $124.80 and Dubai $116.35 (worldoilmonitor), the average is ~$120.6: Medium OSP price ≈ $116.6, less the 25–29.8 spot deduction → net FOB ≈ $86.8–91.6/bbl, an effective net-to-arrive discount of roughly -$29 to -$34/bbl to the Oman/Dubai marker. Heavy is deeper. Even with the tighter OSP table, end-user real discounts remain substantial.

III. Macro & Geopolitics

Brent printed $103.87/bbl (-0.91%) and WTI $99.40 (-2.46%) on Sep 20, sliding four sessions from ~$110 highs back toward $100 (some feeds showed an intraday dip below $100 to $98.85 on Sep 19). What fell was risk premium, not a fundamental reversal.

Hormuz saw only 3 tankers on Sep 17 (conflict-period low); no VLCC has exited the strait since Sep 3. Saudi's East-West pipeline (7 mb/d) is expected to restore ~50% within days and fully in ~6 weeks — a stopgap, not a reopening. Three diplomatic tracks (China urging Iran to restrain Houthis, US Muscat contact, Saudi two-week ceasefire proposal) remain unconfirmed. CapitalEconomics estimates ~8 mb/d of crude still flows via the strait (57% of pre-war).

IV. Practical Notes

Chinese independents (Rongsheng / Shenghong / CNPC) still favor locking Basrah Medium/Heavy term volumes where the discount stack beats spot; but STS premium and war-risk surcharges must be priced in. Watch next week whether Hormuz clears 20 tankers/day with crude carriers returning — the only hard metric not masked by rhetoric. Sources: Argus / chemicalsupdates / Reuters / Jin10 / Sina.