[chakkop]

This is an error in the article, and the responses above are incorrect. 'Ten on thirty' means $10 million invested at a $30 million pre-money valuation, with a post-money valuation of $40 million. This means that the $10 million acquires 25% (NOT a third) of the company.

'Ten on fifteen' would mean $10 million invested at $15 million pre-money, giving $25 million post and the investors 40% of the company. And so on.

Investors almost always speak on a pre-money basis: thus, $15 million pre-money is half of $30 million pre-money.