1) Do commercial property policies include any liability cover? 2) What is the usual basis of cover for each of public liability, product liability, employers liability and professional indemnity?
Yes, normally, liability would either be included in the commercial property cover, or at least added on as a separate cover. Either way, the owner of the commercial property would want liability cover. Theoretically you could get any claims basis for these covers, although my understanding for the norm is losses occurring during for public liability and employers' liability, and claims made for product liability and PI.
