After the WWDC 2011 conference on June 6, Apple announced that anyone who purchased a Mac between June 6 and July 20 will receive Mac OS X Lion for free. Everything happens through Up-To-Date Program, a program launched by Apple specifically for customers who want Lion, have recently bought a Mac and are exempt from paying another $30. To qualify for this program, you must have bought a Mac from the Apple Store or from an authorized reseller's store, including refurbished Macs sold by Apple or resellers.
To get OS X Lion for free you must access this link and fill out the form there, then you will receive a redeem code that you can use in the Mac App Store. This process also works in the case of Mac OS X Lion Server, but you must have bought a Mac on which Mac OS X Server was installed. If you purchased a Mac after July 21st and it came without Mac OS X Lion then follow this link to request a free code.
If your Mac was purchased before June 6, then you must purchase Mac OS X Lion from the Mac App Store.
