Contribution
If you have an idea and you are working with a team of people, there is a way that you can get your idea passed and accepted by others easily. Pitch your idea and ask for any contribution and try to get as many people involved as possible. If they are all working together on your idea it will most likely be accepted.
This is because everyone feels like they are contributing to the idea and that it belongs to them as well. This can also make your idea better by listening to the opinions of others and adjusting your idea in ways you could have never thought of before. So sharing is not all that bad in the end.