How do you determine if a gift is individual giving or institutional giving?

We are having issues with when to record a gift as an individual donor or an institutional gift. Do you have rules to determine which the gift should be recorded as. For instance, Family Foundation and Foundation. If it is from a Family Foundation would you record this as an individual gift or an institutional funder/gift.

In the past, gifts have been recorded based on who has been working with the donor. So we do not have set rules and feathers are getting ruffled on both sides. I have been asked to give advice on how to set these rules and what best practice is.