So you don't know basically? Best to confirm and check.
Also ask them about EU Parent subsidiary directive post brexit for UK company as a holding company for Malta company. Remember EU PSD will no longer apply post brexit to UK companies. However this has no impact I can think of the top of my head as both countries are zero rated for dividend withholding taxes. However there are often odd indirect problems related to UK leaving and not sure if anything will affect Malta's tax treaty with UK but others are affected indirectly i.e after brexit I read.....
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"there may be other indirect treaty consequences. For example, following Brexit, the UK will no longer be an EU Member State for the purposes of applying the limitation on benefits (LoB) clause in US double tax treaties (for example, with Ireland and the Netherlands), such that treaty benefits may in some cases be lost on payments from a US source to a subsidiary of a UK holding company located in those jurisdictions "
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