Sorry Bert and Rapaire, the safety pin (fibula) was around the Mediterranean before the founding of Rome, and before the Celts were in the neighborhood. Earliest are late Bronze Age (2nd. millennium B.C.).

When safety pins were patented in the 1840s, the design was very similar to the early Mediterranean ones. None of the descendants of the guy who filed the patent bothered to sue.

Maybe they were too stuck up to bother.