Netflix believes the winner in the HD format war has been determined and said that it has begun stocking Blu-ray discs exclusively. The company said that its move is prompted by the decision of four out of the six major movie studios to publish high-def DVD titles only in the Sony-developed Blu-ray format. The online movie rental company intends to phase out HD DVDs by the end of this year and, as of now, is purchasing HD titles in Blu-ray only. The firm's current HD DVD inventory will remain available to customers until the discs' "natural life cycle" takes them out of circulation in the coming months. "The prolonged period of competition between two formats has prevented clear communication to the consumer regarding the richness of the high-def experience versus standard definition," said Ted Sarandos, chief content officer for Netflix, in a prepared statement.