Adding any copyright notice is optional since 1989 in the US, the year they joined the international agreement of the Berne Convention which was ratified in 1886 already.
The main purpose today is to demonstrate the owner claims the rights and is actually willing to defend them (in court), but it's not necessary to put it on any work.
From http://www.copyright.gov/title17/92chap4.html#401:
If a notice appears on the copies, it shall consist of the following three elements:
(1) the symbol © (the letter C in a circle), or the word “Copyright”, or the abbreviation “Copr.”; and
(2) the year of first publication of the work
If they haven't touched this page since 2012 (totally reasonable), I think it should be 2012.
This blog post (http://www.photoattorney.com/qa-what-year-should-i-use-for-m...) also mentions that you can use a range for when it covers multiple years of publication (like a blog).