[7] While Matheson's website traces their history back to 1825 and notes that their offices were burnt in the Irish Easter Rising of 1916,[8] it wasn't until after the creation and initial development of Dublin's International Financial Services Centre (or IFSC) that Matheson emerged as a small but standalone law firm with 14 partners and over 50 solicitors (or lawyers) in 1991.

[17][18] Like Feargal O'Rourke in PriceWaterhouseCoopers, Matheson has been an active lobbyist for expanding various Irish legal structures and amending taxation controls to help grow the IFSC, which can lead to conflict.

[26][27] In 2013 the Wall Street Journal ran another investigation showing that the scale of U.S. operations in Ireland, using Matheson registered tax structures, had dramatically increased from 2005.

[32][33] Mainstream U.S. media channels have singled out Matheson in Dublin, as a significant centre for U.S. multinational tax strategies.

[35] Bloomberg recognise that O'Rourke, while being at the vanguard of legitimate but aggressive U.S. multinational tax planning, is considered a "hero" in Ireland.

[62][63] It was revealed in the Irish section of the Panama Papers leak of 2016, that a senior partner in Matheson, Stanley Watson, had established an offshore tax structure with Mossack Fonseca's help in Cyprus, to reduce his tax bill on moving to London to set up the Matheson London office.