At Perfect Audience we told our potential hires this info at the time of giving them an offer sheet. It seemed only fair to let them know how the company was doing and how much money they stood to make from an acquisition.

At the time it seemed like the only fair approach. We founders honestly didn't know that most startups tell potential hires as little as possible about company finances.

Knowing what I know now, I'd still tell folks this info as it unwittingly gave us a hiring advantage over companies that don't.