The paper investigates the linkages between characteristics of technologies and a firm’s knowledge base. Nanotechnologies have been defined as converging technologies that operate as nanoscale, and which require integration to fulfil their economic promises. The paper analyses the degree of convergence and the convergence mechanisms within a firm’s knowledge base. If convergence predominates as it has been claimed, nanotechnologies are not competence destroyers and the development is based on the exetension of the knowledge base of existing firms. Based on a worldwide database of nanofirms, the paper examines the influence of the characteristics of the technologies on the structure of the firm knowledge base. It argues that nano S&T patterns of development combine competence destroying activities and a critical role of research facilities and technological platforms. While the competence destroying characteristics of nanotechnologies give a premium to emerging companies, the role of research and production facilities stenghthens large incumbent competitive position and geographically polarises the emergence of small dedicated nanofirms.