Is there a minimum period of time a business or company/establishment is meant to retain lost property before giving/selling it to someone else or charirty?
'Found property' used to be referred to under the Railway Byelaws but I can't find any reference in the latest (2000) edition. However, the rail company I used to work for retained property for 3 months (which, I believe was the rule under previous byelaws) before disposing of it.
If you've got piles of found property sitting in a cupboard, you're probably safe to dispose of it after 3 months, as this seems to be the maximum time that any organisation hangs on to it.