ownership structure; (ii) firms with a known ownership structure but not belonging to a
business group and, finally, (iii) firms with a known ownership structure and belonging to a
business group. All these data refer to the year 2001.
The resulting sample of the statistical integration of these two sources consists of
511,118 manufacturing firms (with 4,564,891 employees) of which 116,884 (with 3,151,848
employees) have a known ownership structure. Of these 26,181 firms (with 1,863,886
employees) belong to a business group. Thanks to the data drawn from ASIA on the firm’s
geographic location, we also have information about the membership of these firms to the
784 LLSs and, therefore, to the 199 Italian industrial districts identified with the official
statistical procedure previously described.
From the two already mentioned statistical sources is also possible to identify the
business groups, composed by firms belonging to the same owner(s). We have then
isolated the manufacturing business groups defined according to the following two criteria:
i) the group is composed of at least two productive companies, one of which is a
manufacturing firm5; ii) the largest company of the group is a manufacturing firm. A group
is characterized as belonging to a specific sector of activity according to the sector of its
largest company. A manufacturing group is considered as belonging to an industrial district
when the largest company is located in it and it operates in the same sector of the district.
Given these criteria we identified 9,954 manufacturing groups, 1,726 of which belong
to an industrial district. The manufacturing and service firms belonging to these business
groups were 35,040, with an average of 3.5 firms per group. For each business group we
computed the following variables: i) the number of firms in the group; ii) the overall
employees of the group; ii) a specialization index, based on the share of total employees
belonging to the same sector; iii) a location index based on the share of the total employees
belonging to the same LLS.
The distribution of business groups by class of employees and number of firms is
shown in Table 1.
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