How long does it take to apply for a patent license?

Legal analysis: within 3 months.

According to Article 5 of China's Measures for Filing Patent Licensing Contracts, the patent licensing contracts concluded between the patentee and others shall be filed with the Patent Office within 3 months from the date when the contracts come into effect.

Legal basis: Article 5 of the Measures for Filing Patent License Contracts, the parties concerned shall go through the filing procedures within 3 months from the effective date of the patent license contract.