The cross-employment of PhDs across the university sector boundary : an analysis of Finnish register data

Tacit knowledge flows can be facilitated by employment transitions, such as for example the transitions of PhDs from university employment to industry. There are however barriers to transitions into and out of university employment, and as a consequence, such transitions are relatively rare. PhDs can circumvent the barriers to permanent transitions by simultaneous secondary employment relationships. Though we know that such cross-employment exists, we do not know how common it de facto is. In this paper, we use a nine-year panel of daily-level employment microdata on the full population of Finnish PhDs to show that about 30% of university-employed PhDs are cross-employed outside of universities. This is a substantial share, and its magnitude alone suggests a central but underappreciated role for cross-employment in contemporary knowledge production and dissemination. We furthermore find that similar numbers of non–university-employed PhDs are cross-employed at universities as university PhDs are cross-employed outside of universities, and that many cross-employment relationships are in non-technical fields, and with public sector organizations. This illustrates the importance of understanding the nature of knowledge flows other than the unidirectional flows of technical knowledge from universities to industrial firms.