This data-file tracks 110,000 solar patents filed by geography, by company, by year, since 2000; but particularly in 2019.
Solar patent filings peaked in 2012-13 at 11,500 patents per year. Many geographies have since slowed by 50-90%; except China, which hit a new peak off 3,500 patents in 2019, leading the industry.
A granular breakdown for 2019 tabulates 6,000 patents, including their descriptions, which you can interrogate fully. 14 out of the top 25 solar patent filers in that year were Chinese companies.
The largest US and European patent filers are also shown. So are the Majors, which have recently filed c30 patents per year (0.5% of the total), two thirds of which can be attributed to a single SuperMajor, looking to scale up in solar.