After reading old IO interviews all the way from late 1990s to early 2000s, it hit my mind ''What do the company’s initials stand for anyway? Naturally, the employees and members of any given company change over time, so i wouldn’t be surprised if none of the current IO devs knew the answer.
I suppose the best way to get an answer to this would be to contact Codename 47’s writers, Peter Koch and Morten Iversen, or the original founder of IO, Jesper Jørgensen.
I recall there being maybe 1 or 2 topics concerning this matter in the old Hitman Forum. But other than that, fans have seldom cared.