“…Macro‐level studies on EU interest organization populations either rely on categorizations of interest organizations that neglect firms altogether, focusing exclusively on associations representing business interests and non‐governmental organizations (NGOs) (Berkhout and Lowery, 2010; Berkhout et al ., 2015; Beyers 2004; Carroll and Rasmussen 2017; Dür et al ., 2015; Dür and Mateo, 2016; Hanegraaff and Berkhout, 2018; Wonka et al ., 2010), or rely on a cross‐sectional designs that make it impossible draw inferences on over‐time variations in the relative presence of firms within such communities (see Berkhout et al ., 2018). A number of micro‐level studies investigating the determinants of firms' choices to engage in direct lobbying have recently contributed to shedding systematic light on the role of firms in the politics of interest representation in the EU (Bernhagen and Mitchell, 2009; Dellis and Sondermann, 2017). Yet, again, the cross‐sectional design of these works, as well as their exclusive focus on firms, make them ill‐equipped to shed light on whether the share of firms lobbying in the EU increased over time relative to other interest organizations.…”