That's a very real concern for us. We are taking a few measures for this and are continuing to look into this.
- As soon as a logo is purchased with a unique icon, we delete that icon from our data.
- We manually go through our icon repositories and try to find icons that have already been used in logos and delete them.
We'll continue doing this until we are left with stuff that has not been used anywhere else in a logo.
A bit part of logo design is ensuring that it can be trademarked, so this is pretty important.