Abstract:     Diversification or specialization is a common choice of firms for their technological layout strategies. Extant studies focus either on diversification or on specialization, which are seemed incompatible strategies for firms. However, diversification and specialization are not two ends of the same dimension. A high degree of diversification does not mean a low degree of specialization, and vice versa. Thus, this paper combined diversification with specialization and extended the technological layout strategy of firms to the “T” shaped strategy. The “T” shaped strategy means that a firm not only focuses on deeply cultivating its core technological fields, but also broadening to other related or unrelated technological fields when choosing a technological layout strategy. Moreover, the prior literatures suggested that collaborations have impacts on the technological layout of firms, but scholars only paid attention to the influence of characteristics of collaboration, such as the alliance type, the degree of internationalization and technological distance, etc. The degree of familiarity and competition between the focal firm and its collaboration partners are ignored, and how these characteristics of R&D collaborations influence the technology layout strategy of firms is less studied until now. In reality, more and more firms form the “T” shaped strategy relying on R&D collaborations, especially for autonomous driving firms which facing on high uncertainty and technological complexity. In the field of autonomous driving, inter-firms both compete and cooperate. How the conflicts of interest between competitors affect the knowledge acquisition in the process of R&D collaborations? Whether repeated collaboration can improve mutual trust? These queries will pose new challenges for the question how R&D collaboration affects the technological layout of autonomous driving firms.Therefore, from the perspective of new/old partners and competitive/non-competitive partners, this paper investigated how R&D partner selection influences the formation of diversification, specialization and the “T” shaped strategies of autonomous driving firms. Using a sample of Chinese and American autonomous driving firms,and collecting the panel data from 2011 to 2020 for an empirical analysis,this study reached the following new findings: first, R&D collaborations with new partners and non-competitive partners can both help firms broaden technological fields and then form the diversification strategy. Second, R&D collaborations withboth former partners and competitive partners have no significant impacts on the specialization strategy of firms. Third, R&D collaborations with newly competitive partners are conducive to the focal firm forming the “T” shaped strategy. Finally, there are significant differences between Chinese and American autonomous driving firms considering the effects of R&D collaborations on technology layout strategies. Specifically, Chinese autonomous driving firms collaborate with new R&D partners have more significant effects on the diversification strategy than American firms. Besides, Chinese autonomous driving firms collaborate with newly competitive partners have more significant effects on the “T” shaped strategy than American firms. These findings will make contributions to the literature on R&D collaborations and technological layout strategy of firms. First, the present study extended the technological layout strategies of firms from diversification or specialization to the “T” shaped strategy. Second, this paper explored how R&D collaborations have impacts on the diversification, specialization and the “T” shaped strategies of firms, which enriches the relationships between R&D collaborations and technological layout strategies of firms. 

Key words: R&D collaboration, technological layout, diversification, specialization, “T” shaped strategy, autonomous driving