I never understood these ~13.3x valuations. If I invest $5 in a lemonade stand, what makes it valued at $66.50?
I invest $10 in a lemonade stand and get 10% equity in the company. That means that I can theoretically buy the company at $100 to get 100% of the equity.
So when investors put $150M into a company, they are purchasing equity/stock/shares/whatever and the company can then be valued based on the percentage of equity they get for their investment.