Pattern on top of egg

[cochinator]

This is a giant egg from a barred rock that is about 3 years old. Anyone every seen a pattern like this on top and what does it mean.

 

[Kelsie2290]

http://www.thepoultrysite.com/publications/1/egg-quality-handbook/20/bodychecked-eggs
They call that a body checked/wrinkled/corrugated egg, here is The Poultry Sites page for the body checked eggs. It has to do with damage to the egg while in the shell gland from various causes. Age often seems to bring them on and older birds lay them more often, I get them a lot from my old commercial White Leghorns. They are fine to eat, the shell just tends to be fragile on the wrinkles.
http://www.alltech.com/sites/default/files/alltech-egg-shell-quality-poster.pdf