Abstract: Abstract: The sleeping patents are referred to neither actively exploiting patent nor negatively utilizing patent, and blocking patents and problem patents are excluded from them. The basic condition for sleep patents in China is analyzed, the reason for existence of sleep patents is explained by the theory of transaction cost; it is considered that sleep patents is the outcome of lack complementary assets and high transaction cost. And some preventing and cueing strategies are put forward.

Key words: sleeping patent, transaction cost, complementary asset, prevention