TAX IMPLICATIONS
Either way (private vs. public), you are taxed on dividends and capital gains (when you sell).
As an accountant, I would be hesitant to give away my SS# as I have seen many fraud issues when filing tax returns, etc.
As far as liabilities go, Corporations are generally safe bets for gifts of equity (the Corporate veil will protect you). Partnerships, on the other hand, turn to partners when the Company goes bankrupt and defaults on it's obligations (depending on basis, legal structure, etc.).
Not sure what EPGL & this new Company are trying to accomplish (besides logistical synergies, making more moolah, and so on) without knowing the corporate structure.
I still have not decided what to do. Maybe if the Company was a bit more forward with details, but here lies the classic risk/reward function.....