Ideas Are Cheap; Execution Is Key
I believe there's no harm in sharing, even if it's just in the initial stages. As the saying goes: Ideas are cheap, execution is key. If you believe you're into something that could positively impact a business process or an aspect of people's lives, do thorough research of your industry of interest and the existing market players.
Most importantly, reach out to potential users to better understand their needs. These are prior steps to ensure that you're creating a solution to a real and existing problem.