Who owns backlinks?

If you pay a company to carry out SEO, including link-building using links within content on blogs; who owns the links when the contract ends?

Bearing in mind the SEO company charge a day rate, and don't specify how they would build links.

If these were paid links bought through a link vendor, then obviously they would be removed as soon as payment ended. However, if the links are on blogs owned by the SEO company, can they be removed at the end of the contract?

All opinions/views appreciated.

I suppose they send you a contract, no? Read all If they post on their own blog I Supose that they tell you how long the link stay on their blog.