Spanish newspaper El Confidencia alleged Ronaldo had benefited from keeping assets in a tax haven.
They have respected "fully their obligations regarding Spanish and British authorities," read a statement for Gestifute, run by their agent Jorge Mendes.
Spanish newspaper El Confidencial, quoting documentation from the Football Leaks website, alleged Ronaldo had benefited from keeping assets in a tax haven.
The website said the footballer of the year favourite had used Irish-based Multisports & Image Management Limited to ramp down his tax burden below what he would have been subject to in Spain.
Gestifute complained it had faced "insidious," "disrespectful" and "threatening" questioning from the media over its clients' tax arrangements since last year's Panama Papers scandal surfaced.
Gestifute said neither Ronaldo, nor his Portuguese compatriot and former Real coach Mourinho were "implicated in any judicial procedures".
Gestifute added that last March "a number of societies linked to the world of football were the victims of cyber-attacks" which saw the leaking of documents published by Football Leaks "in several countries in Europe, notably Spain."
The company noted they had taken legal redress against claims of tax evasion and stressed it had always acted with "the highest degree of professionalism in relations with (its) clients and authorities".