[graeme]

Not in every country, and secondly if you're basing it on life of the author then that does't solve corporate copyright unless you tie it to the live of a particular employee.

You could do "life of author or X years, whichever is longer". Or include a period after death.

But you see how the complexities come in.

[clort]

The complexities are the problem. I've always thought a fixed term is best. Then, you can purchase a work - it says Copyright <dddd> on it. Then, you know that after dddd+term the copyright is lapsed. You don't need to hunt down the author to see if they died. No guessing, just written on the work that you purchased. No, don't have optional extensions - that just means you have to look it up. It should say it right there on the work you purchased when the copyright expires.

It is said that the vast vast majority of works don't earn anything significant after a few years in any case, meaning the only possible reason to have long copyrights is so that a very few people can get stinking rich. But those people already got rich, in the first few years.. society does not benefit from them getting richer.

20 years fixed term is my proposal.