Why does China, despite leading in new application volume, often rank below the US and Japan in total patents *in force*?

Answer

China’s massive surge in filing is relatively recent.

China's high filing volume is recent, meaning many applications have not reached the stage where renewal decisions—reflecting long-term commercial commitment—are being made over several years.

Why does China, despite leading in new application volume, often rank below the US and Japan in total patents *in force*?
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