Sun raised its posted price for domestic crude oil.

The Radnor, Pa.-based oil company said it will pay $27.50 for a barrel of West Texas Intermediate, an increase of 25 cents. Sun Oil said it raised the price in response to market conditions. Crude oil prices firmed on the spot market as oil companies continued to build crude oil inventories. Crude oil for October delivery closed at $27.97 a barrel, up 9 cents.