Redmond (WA) – Microsoft has a special way of saying thank you to the company that has built the foundation for a $1 billion franchise.

With Halo 3 achieving more than $300 million in sales within the first week after launch, developer Bungie Studios apparently had enough reasons to reconsider its relationship with Microsoft. According to a press release issued today, Bungie will become an independent company again. The company, founded in 1991, had been a subsidiary of Microsoft since 2000.

Microsoft said that it will retain an equity interest in Bungie and continue its publishing agreement between “Microsoft Game Studios and Bungie for the Microsoft-owned ‘Halo’ intellectual property, as well as other future properties developed by Bungie.”

"Our collaboration with Bungie has resulted in ’Halo’ becoming an enduring mainstream hit," said Shane Kim, corporate vice president of Microsoft Game Studios. "While we are supporting Bungie’s desire to return to its independent roots, we will continue to invest in our ’Halo’ entertainment property with Bungie and other partners, such as Peter Jackson, on a new interactive series set in the ’Halo’ universe,” he said.

Bungie Studios will remain in its current location in Kirkland, Washington.

The new agreement between Microsoft and Bungie appears to have been final for some time. According to a recent blog post on the website of the Seattle Post Intelligencer, the announcement was delayed until today in order to avoid an impact on Microsoft’s Q3 result.