Knowing brown and inventing green? Incremental and radical innovative activities in the automotive sector
研究了汽车企业在低排放车辆两种绿色技术轨迹（改进内燃机与开发混合动力/电动/燃料电池车）中的创新行为，发现棕色领域（传统技术）的知识积累有助于企业在绿色专利中取得领先地位。
The development of low emission vehicles (LEVs) represents a typical case of technological competition between two green trajectories. On the one hand, the incremental trajectory aims at improving the efficiency of the dominant design, greening the internal combustion engine (ICEG). On the other hand, the radical trajectory targets the progress of hybrid, electric and fuel cell vehicles (HEF). This paper studies the innovative behaviours of firms in the automotive sector patenting in both trajectories. It investigates the extent to which technological leadership in green patents is rooted in firms’ knowledge and capabilities accumulated in brown domains. Using a novel dataset of automotive firms with patenting activity at the United States Patent and Trademark Office (USPTO) between 2001 and 2018, we find that related ‘brown knowledge’ denotes leadership in green trajectories.