Noting license/copyright in files

Juan has pointed out that it evidently takes more than just adding a LICENSE file to be under the LGPL...

From https://www.gnu.org/licenses/gpl-howto.en.html :
Whichever license you plan to use, the process involves adding two elements to each source file of your program: a copyright notice (such as “Copyright 1999 Terry Jones”), and a statement of copying permission, saying that the program is distributed under the terms of the GNU General Public License (or the Lesser GPL).

So the question becomes: what do we put in the header? Tor's looks like...

/* Copyright (c) 2001 Matej Pfajfar.
 * Copyright (c) 2001-2004, Roger Dingledine.
 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
 * Copyright (c) 2007-2012, The Tor Project, Inc. */
/* See LICENSE for licensing information */

I'm not a fan of dirtying our source code with legal stuff, but oh well. Questions that I have are...

• Should the start year of the copyright date be the year that stem was started? When the file was created? Something else?

• Does this mean that I need to remember to update the end date every year?

• Until #7566 (closed) I had stem's copyright but now it's a little more confused. I suppose this means a copyright line for both Sean and me in the files that we've both touched?

• I like Tor's "See LICENSE for licensing information". Is that ok or do we need to say "LGPLv3 or later".

Cheers! -Damian