Short answers, pulled from the story.
Howard Schultz sold the Seattle SuperSonics to an investment group led by Clay Bennett on the 18th of July 2006 for $350 million. This transaction followed years of financial losses and a failed attempt to secure public funding for KeyArena renovations.
The city of Seattle filed a lawsuit against Professional Basketball Club LLC on the 23rd of September 2007 to enforce the team's lease through 2010. The court ruled that occupancy rights ended on the 30th of September 2010, but the ownership group eventually paid $45 million to break the lease on the 2nd of July 2008.
NBA owners voted 28-2 to approve the potential move to Oklahoma City on April 18, with only Mark Cuban of the Dallas Mavericks and Paul Allen of the Portland Trail Blazers opposing the decision. This approval allowed the Sonics to begin play at the Ford Center starting with the 2008, 09 season once a settlement was reached.
Voters in Seattle passed Initiative 91 to prohibit using public money for sports arenas after Howard Schultz failed to secure $220 million in funding for KeyArena renovations. This measure effectively blocked any local government support for a new facility and forced the ownership group to explore relocation options.
The Sonics' name and colors could not be used by the Oklahoma City team but remained available for future use in Seattle under the terms of the settlement agreement. Franchise history would be retained by the new Oklahoma City team while potentially shared with any future Seattle franchise.