Shipping licenses may be issued to legal persons and economic organizations established in Hungary and operating shipping vessels registered in EEA states. In order to register a seagoing vessel in Hungary, the vessel must be in majority EU ownership. Cabotage by non-EEA vessels is restricted and is subject to reciprocity.
"12. §  
(1) An inland waterway vessel, seagoing vessel or floating equipment the operation of which is subject to a navigation license shall be entered in the Hungarian register by the maritime authority, unless otherwise provided by an international treaty, if its Hungarian or Community ownership exceeds 50% and the floating facility is not registered in another register.
[...]
13. §  
(1) For the purposes of the registration rules of this Act, Hungarian or community property:
a) a citizen of Hungary, a citizen of a Member State of the European Union or another state party to the Agreement on the European Economic Area, or a party to the Agreement on the European Economic Area under an international agreement concluded between the European Community and its Member States and a state not party to the Agreement on the European Economic Area owned by a person of the same status as a national;
b) owned by  legal entities domiciled in Hungary, a Member State of the European Union, another State party to the Agreement on the European Economic Area or a state of which the European Community and its Member States and a State not party to the Agreement on the European Economic Area are nationals shall enjoy the same status as a national of a State party to the Agreement on the European Economic Area, hereinafter referred to as "the EEA State".
(2) Hungarian or community ownership shall be certified by documents.
(3) Company may be considered to be owned by Hungary or the Community if the share of ownership of a foreigner who is not domiciled or a citizen of the EEA state on the basis of his or her membership or the degree of voting rights exercised by him or her does not reach 50%. five.
[...]
§ 51. 
(1) Shipping activities may be carried out in possession of a shipping license.
(2) No navigation permit is required:
(a) shipping activities with floating facilities not subject to registration,
b) to perform the statutory tasks of central budgetary bodies with their own resources,
c) for the   recreational use of  watercraft, excluding shipping for educational purposes,
(d) the operation of a floating installation as an accommodation or a port, as part of a shipping facility, other than for economic purposes,
(e) for a shipping activity carried out on the basis of a navigation license issued by the shipping authorities of the EEA States.
3. The navigation license shall specify the activity and area to which the license relates and the conditions for the pursuit of that activity.
(4) The maritime authority and the police law enforcement body of the police are entitled to check whether a floating facility carrying out a shipping activity classified as subject to a permit in the territory of Hungary has a permit entitling it to carry out the activity. If a floating establishment carrying out an activity subject to a permit does not have a permit entitling it to carry out the activity, the water authority of the police shall immediately notify the maritime authority.
(5) The maritime authority shall keep a register of issued navigation licenses, which shall include:
a) the name of the driver,
b) the authorized shipping activity,
c) the registration number, name or mark of the floating facilities operated,
(d) the water area (river, lake, river kilometer, etc.) in which the authorized shipping activity may take place,
e) the period of validity of the navigation license,
f) an indication of the Hungarian ownership share of the applicant shipping company and the floating facility used for the shipping activity.
(6) resulted in the shipping register of licenses paragraph (5) in respect of information contained - in paragraph (5) a) of the exception contained data - considered as official records of public credibility.
§ 52. 
(1) navigation license may be issued to a legal person and economic organization established in Hungary operating a floating facility registered in an EEA state.
[...]
§ 54.  
(1) between ports located within the borders of the country by a floating establishment not flying the flag of an EEA State
(a) the carriage of passengers, the carriage of goods and the conveyance of floating facilities in connection therewith,
(b) work on floating equipment
(hereinafter together with points ( a) and (b) together: cabotage) is an activity subject to authorization.
(2) The maritime authority shall issue the cabotage authorization, unless otherwise provided by an international agreement, in the event of reciprocity and in the event that a floating facility registered in an EEA State is not available to carry out the activity.[...]" (Law on the management of water transport (XLII of 2000), last amended 1 July 2021, §§ 12, 13, 51, 52 and 54 [google translation])
Law on the management of water transport (XLII of 2000), last amended 1 July 2021, §§ 12, 13, 51, 52 and 54 
[<a href="https://njt.hu/jogszabaly/2000-42-00-00">Law</a>]