Green hydrogen is emerging as a promising clean energy carrier to combat carbon emissions in challenging sectors like heavy industry and transportation. With global demand projected to rise significantly by 2050, innovations and investments in green hydrogen technology are vital. Hydrogen is categorized into grey, blue, and green types based on production methods, with green hydrogen produced by electrolysis being the most eco-friendly but facing hurdles like high costs and infrastructure requirements. Electrolysers, such as alkaline, polymer electrolysis, and solid-oxide cells, are crucial for green hydrogen production, with solid-oxide technology showing promise due to its efficiency improvements. Patent activity related to green hydrogen has surged in the past decade, with Chinese entities dominating the field. However, multinational companies are also actively involved in patenting green hydrogen technologies. To fully realize the potential of green hydrogen, continued investment, research, and patent protection are necessary for innovators to drive the transition towards a net-zero future.