I need to preface this post with the statement that I am not a lawyer,
and that I am not speaking on behalf of my dayjob employer.

There is no need to include the year in a copyright declaration
statement. And related, there is no need to update the year
statement, add new year statements, manage year range statements, or
any of that stuff. It is tedious, boring, adds no value, and prevents
no risks.

Several large legally sophisticated companies, include Amazon, Google,
Microsoft, and Facebook, are now publishing open source code with
copyright statements without a year.

And so, I have added the following to our devel/hacking document.

Do not specify a year in a copyright statement. Most of the existing
copyright statements already present in the project have been scrubbed
of the year. There is no need to specify the year in a copyright
statement. Several large legally sophisticated companies, include
Amazon, Google, Microsoft, and Facebook, are now publishing open
source code with copyright statements without a year. We encourage
the larger open source community to emulate this.

Being able to do this now has taken a surprisingly large amount of
work behind the scenes, especially on the part of those large
companies. Do please take advantage of it, and write simpler
copyright statements in your open source projects from now on.