 On April 6 , 2009 , Wizards of the Coast suspended all sales of its products for the Dungeons & Dragons games in PDF format from places such as ONEBOOKSHELF.com and its subsidiaries RPGNow.com and DRIVETHRURPG.com. This coincides with a lawsuit brought against eight people in an attempt to prevent future copyright infringement of their books , and includes the recent 4th edition Dungeons & Dragons products that were made available through these places as well as all older editions PDFs of the game . 
