Idem Sonans - United Kingdom

United Kingdom

Under UK jurisdiction, there has been an incredibly small amount of judicial activity here. The old judgment of R v Davis provides:

"If two names spelt differently necessarily sound alike, the court may, as matter of law, pronounce them to be idem sonantia; but if they do not necessarily sound alike, the question whether they are idem sonantia is a question of fact for the jury".

The modern case of Re Vidiofusion Ltd establishes a four stage test when a name of a company is spelled differently in writing:

• No Company of a similar name
• Idem Sonantia - similar pronuniciation
• No marked vision difference (judge gave example of Jackson/Jaxon being too dissimilar visually)
• Misspelling does not substantially change the placement of the name if placed in a alphabetical list.