5 of Ferrari's Design Contest models were patented?

Nothing recent, but it begs the question why these were the only models of Ferrari's design contest winners to actually have a Ferrari patented design....

1) http://www.patentgenius.com/patent/D576523.html

2) http://www.patentgenius.com/patent/D550126.html

3) http://www.patentgenius.com/patent/D550124.html

4) http://www.patentgenius.com/patent/D550125.html

5) http://www.patentgenius.com/patent/D576523.html

Though they were all filed Oct. 26th 06, #5's patent was issued nearly a year after the others. I know nothing about patents, but I thought I'd point that out....