· Global base oils margins stay more mixed but mostly hold at levels that sustain incentive for refiners to maintain firm output of the lubricants feedstock..· Fob Asia light-grade base oils price-premium to Singapore gasoil extends rise, while heavy-grades stay more rangebound. .· FOB Asia Group II light-grade price-premium to gasoil rises to highest since H1 June 2025.· Light-grade price-premium rises faster than in US and Europe, but from lower level.· Higher light-grade price premium partially counters impact of recent rise in gasoil premium to crude.· Higher light-grade price-premium could curb any incentive for refiners to focus on producing more diesel rather than light-grade base oils.· Higher light-grade price-premium balances out recent weakness of heavy-grade base oils price-premium, leaving margins at levels that likely sustain incentive to maintain high total output levels. .· China's domestic Group II N150 price-premium to Shandong diesel price rises, breaking out of recent, low range since H2 June 2025..· Price-premium rises at a time of year when buyers typically start to replenish stocks ahead of seasonal rise in demand in late-Q3.· Lower price-premium in recent weeks could have incentivized refiners to keep output at lower levels.· Lower output could magnify impact of pick-up in demand.· Any rapid reversal of price-premium in coming weeks could conversely point to sufficient supply or weaker-than-expected seasonal rise in demand..· CFR India Group II N70 price-premium to Singapore gasoil price rises to highest in more than two months..· Higher price-premium facilitates arbitrage, incentivises overseas refiners to supply more very-light grade base oils.· Higher price-premium points to firm demand, with outright prices ignoring any pressure from weaker gasoil prices..· Europe’s Group II heavy-grade price-premium to vacuum gasoil (VGO) edges up after slipping in July 2025..· Group II heavy-grade price-premium stays unusually high even after slipping in July 2025.· Group II heavy-grade price-premium to VGO continues to rise faster than Group II light-grade and Group I heavy-neutrals price-premium to VGO.· Dynamic points to increasingly firm supply-demand fundamentals for Group II heavy grades relative to feedstock prices, relative to other grades and relative to other regions..· US Group II light-grade export price-premium to VGO holds close to lowest since Q1 2025, when fundamentals were seasonally weak.· US Group II light-grade domestic price-premium to VGO holds in relatively narrow range, above lower levels in Q1 2025 but below levels in Q3 2024..· Steady-to-firm light-grade domestic price-premium to VGO curbs pressure on refiners to adjust output.· Sliding export price-premium to VGO could point to moves to maintain more balanced domestic fundamentals by clearing surplus volumes through the export market..Asia base oils demand outlook: Week of 11 August.Asia base oils supply outlook: Week of 11 August.Base Oil News stories and analysis also available on ICIS platform