“…Because of the lack of precise geolocated data, research is generally conducted either on aggregated data at regional or national level, on panel data for several years (Demzetz and Lehn, 1985) or for one specific sector only (Franks and Mayer, 1997;Bond et al, 2006;Watts et al, 2007). Studies on ownership links of firms at city level have been conducted for all types of sectors for different geographical areas (Gillespie, 2017;Martinus et al, 2019;Rozenblat, 2010;Rozenblat et al, 2017;Rozenblat and Pumain, 2007;Śleszyński, 2015;Zdanowska et al, 2020;Zdanowska, 2020) with the objective of modeling growth of urban firm networks (Raimbault et al, 2020) . Ownership and industrial linkages have already been studied in Northern England, but for regions only (Marshall, 1979).…”