Okay, #3 in NASCAR is owned by Richard Childress Racing with typeface and everything.

They went as far as to sue ESPN for copyright infringement for the use of the #3 logo in their Dale Earnhardt biopic, according to Wikipedia.

Now, F1 driver Daniel Ricciardio used the exact typeface and colour scheme for his choice of #3 on his helmet (as drivers in F1 are now allowed to chose their numbers), except it uses the reversed italics version of the same font that is usually associated with the Earnhardt #3 logo, but was painted in the same manner on the right side of the Richard Childress car for symmetry (and is used by Austin Dillon currently after a 13-year absence).

I don't know about international patents and copyrights, but I doubt this helmet and logo would pass in the US without getting the same treatment as ESPN did, it should be interesting to see whether the NASCAR community will take this little pseudo-homage as trespassing in their back yard.