Foreign investment of any kind in Italy is subject to a reciprocal treatment of Italian citizens and legal persons in the relevant foreign country. Note that EU and EEA citizens and citizens of a country that has entered into a bilateral investment agreement with Italy are exempt from this requirement.
"Art. 16. (Treatment of the foreigner). 
The foreigner is allowed to enjoy the civil rights attributed to citizen on condition of reciprocity and subject to the provisions contained in special laws. 
This provision also applies to foreign legal persons.[...]" (ROYAL DECREE March 16, 1942, n. 262, "Approval of the text of the Civil Code"; in force from 19 April 1942; Article 16 [google translation])
ROYAL DECREE March 16, 1942, n. 262, "Approval of the text of the Civil Code"; in force from 19 April 1942; Article 16
[<a href="http://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1942-03-16;262">Decree</a>]