You can remove stars that you have added to entries by mistake. Color stars that are removed from entries cannot be reused.
When you add color stars to another user's entry, the other party is unable to reuse the color stars that he or she has received.
Color stars that you have purchased can only be used by your currently logged in Hatena account. If you wish to use color stars with your sub-account, you need to purchase color stars from your sub-account.
The creator or administrator of certain Hatena Diary, Hatena Group and other blog services may choose to use images other than the standard Hatena stars on their pages. Please be advised that your color stars will not be displayed on these types of pages.
If you close your account your color stars can no longer be used.