One thing I wish to know is whether it is possible to negotiate the terms so you have preference of liquidating some of your shares when company raises a round

One thing I wish to know is whether it is possible to negotiate the terms so you have preference of liquidating some of your shares when company raises a round. Surely, the possibility of an IPO or an acquisition might be uncertain but another funding round seems a very plausible event. One company, Atlassian, did raise one round solely to allow employees to vest their shares but I am not sure how common this is in Silicon Valley's Tech Culture.