Expatents returns a list of patents expiring that day and you can sign up for a weekly digest of expiring patents.
The site claims that over 80% of patents are never commercially exploited.
Are expired patents, that is without commercial exploitation, like articles that are never cited by anyone?
Potential shareholder litigation over the not-so-trivial cost of patents that never resulted in commercial exploitation?
Was it inside or outside counsel that handled the patent filings?
There’s an interesting area for tracing relationships (associations) and expenses.