The legal conception of contra legem derives from Roman law and is translated into "against the law". A decision contra legem arises when the text of law and the legislators purpose of law are disregarded. A paradoxal consequence is that there will always be a decision contra legem, when the text of lawand the legislators purpose of law are contradictory. It is therefore important that decisions contra legem are based on legitimate motives to ensure law and order. In fraudem legis is another legal conception from Roman law and is translated into "evasion of law".

According to the arm?s length principle, transactions between associated multinational en-terprises (MNE) shall be based on the same conditions as transactions between unrelated parties. This means that intra-group prices on cross-boarding transactions must be at arm?s length range and consistent with conditions in the open market. The arm?s length principle is expressed in article 9.1 of the OECD Model Tax Convention and Chapter 14 section 19 of the Swedish Income Tax Act.When transfer pricing between associated MNEs is not reflecting the arm?s length princi-ple, states face the possibility of losing tax revenue.