You can put some code to guarantee using your application the main spiders index the content before anybody else. The problem is scrappers can monitor and fetch your content way faster than spiders.
There are various ways doing this without getting implicated with cloaking. For example publishing via the SEs sitemap, once the page is indexed you update the site navigation so the page can be found by everyone.
If somebody else fetches your content and publishes it first, before SEs, you have a very hard time convincing anyone its yours unfortunately.