Johansen is a self-trained software engineer, who quit high school during his first year to spend more time with the DeCSS case.

[5][8][9] The trial opened in the Oslo District Court on December 9, 2002, with Johansen pleading not guilty to charges that had a maximum penalty of two years in prison or large fines.

Although these resulting raw AAC files were unplayable by most media players at the time of release, they represent the first attempt at circumventing Apple's encryption.

On March 18, 2005, Travis Watkins and Cody Brocious, along with Johansen, wrote PyMusique, a Python based program which allows the download of purchased files from the iTunes Music Store without DRM encryption.

In late 2005, Håkon Wium Lie, the Norwegian CTO of Opera Software, co-creator of Cascading Style Sheets and long-time supporter of open source, named Johansen a "hero" in a net meeting arranged by one of Norway's biggest newspapers.

[17] On September 2, 2005, The Register published news that DVD Jon had defeated encryption in Microsoft's Windows Media Player by reverse engineering a proprietary algorithm that was ostensibly used to protect Windows Media Station NSC files from engineers sniffing for the files' source IP address, port or stream format.

[20] In November 2005, a Slashdot story claimed that Sony-BMGs Extended Copy Protection (XCP) DRM software includes code and comments (such as "copyright (c) Apple Computer, Inc. All Rights Reserved.")

[24] In October 2006, Johansen and DoubleTwist Ventures announced they had reverse engineered Apple Computer's DRM for iTunes, called FairPlay.

Rather than allow people to strip the DRM, DoubleTwist would license the ability to apply FairPlay to media companies who wanted their music and videos to play on the iPod, without having to sign a distribution contract with Apple.

[27] In June, he managed to get an advertisement for his application doubleTwist on the wall of the Bay Area Rapid Transit exit [28] outside the San Francisco Apple Store, just days before the 2009 WWDC event.

[29] On June 9, it was reported that the advertisement was removed by BART for allegedly "being too dark" and not allowing enough light into the adjoining transit station.