According to this SEC filing, Varien has raised $22.5 million in an equity deal to an undisclosed investor. According to TechCrunch, it may very well be Paypal, who has been collaborating with Magento on product development since 2008.
Magento builds momentum by leveraging the power of open source
One example of a rapidly-growing open source eCommerce platform solution is Magento Commerce, which is developed by L.A.-based Varien.