The purchase by foreigners other than EU residents of a majority interest in Italian flag vessels is restricted. Fishing in territorial waters is reserved for nationals and national fishing vessels.
" Art. 4. Fishing license
1. Ships and floats authorized to navigate, pursuant to of article 149 of the navigation code, for the exercise of professional fishing must have a fishing license." [...] (LEGISLATIVE DECREE 26 May 2004, n. 153 "Implementation of the law 7 March 2003, n. 38, concerning sea fishing"; last amended by DECREE-LAW 18 October 2012, n. 179; Article 4 [google translation])
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"Art. 143. (((Nationality requirements of owners of Italian ships).)) 
((1. They meet the nationality requirements for enrollment in the freshmen or in the registers referred to in Article 146: 
a) ships belonging to more than twelve carati to natural persons, legal entities or entities in Italy or in other countries of European Union; 
b) ships newly built or from a register non-EU foreigner, belonging to natural or legal persons or non-EU foreign bodies which hire directly the operation of the ship through a permanent establishment on the national territory with management entrusted to a natural person o  juridical of Italian nationality or of other countries of the Union European, domiciled in the place of registration of the ship, which it hires any responsibility for its exercise towards the administrative authorities and third parties, with a declaration to be made at the ship's registration office, according to the established rules for the declaration of owner.)) 
[...]
Art. 149. (Authorization of ships for navigation). 
The ships registered in the freshmen and the ships and the floats registered in the registers are enabled to browse respectively from the nationality certificate and from the license.
To this effect, the deed of nationality can be temporarily replaced by a temporary gangway, and the license by a license provisional. 
[...]
Art. 221. (Fisheries reserve for citizens). 
Fishing in the territorial sea is reserved for Italian citizens e to national fishing vessels, except for special agreements international. 
However, citizens can be authorized by royal decree ships of States, with which such conventions do not exist, ad fishing in the aforementioned waters.[...] " (Navigation Code (ROYAL DECREE 30 March 1942, n. 327), last amended by DECREE-LAW 14 August 2020, n. 104, Articles 143, 149 and 221 [google translation])
LEGISLATIVE DECREE 26 May 2004, n. 153 "Implementation of the law 7 March 2003, n. 38, concerning sea fishing"; last amended by DECREE-LAW 18 October 2012, n. 179; Article 4
Navigation Code (ROYAL DECREE 30 March 1942, n. 327), last amended by DECREE-LAW 14 August 2020, n. 104, Articles 143, 149 and 221
[<a href="http://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2004-05-26;153!vig=2021-08-19">Decree</a>],[<a href="http://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1942-03-30;327!vig=2014-09-12">Code</a>]