Positive rights are privilidges that are claimed to be rights. A positive right is one that requires another entity to do something in order to fulfill the right. A good example is the right to eat. You have the right to eat. You don't have the right to food. The second requires someone else to provide you with food. The maxim that "positive rights don't exist" means that a right isn't really a 'right' if it requires someone else to do something.