Re: Adding missing copyright years

[Richard Stallman]

    In addition, Richard has told me that multi-line copyrights are OK,
    and you can use two-digit years as long as they are bracketed by
    matching four digit years (for example, 1996, 97, 98, 1999, 2000, 01,
    02, 2003).

That was what a lawyer told me several years ago, but more recently (a
year or two ago) Eben Moglen said it was better to write each year
number completely.