• Knowledge Spillovers
• Product Market Space
• Technology Space

This study aims at exploring empirically the relationship between knowledge spillovers and firm performance. The investigation is carried out on a firm-level panel data set covering 31 OECD countries in the 2009-2018 period. Exploiting and adapting Bloom, Schankerman and Van Reenen's (2013) empirical framework, we estimate the effect of knowledge spillovers coming from technological neighbours and product market rivals on a range of firm performance indicators (market value, patent counts, productivity). We further analyse heterogeneity in the emergence of the effects, by re-estimating our models on subsamples of our firm population, identified by employment size cohorts or by clusters of technologically homogeneous sectors. At the full sample level, we observe a positive effect of technological spillovers on each of the outcome variables, while product market rivalry effects are insignificant. The split sample analysis highlights the presence of firm size- and sector-specific dynamics in the estimated effects, suggesting the need for an explicit account of their extent and of the factors which cause them.