Microsoft, once a staunch opponent of open-source technology, is joining the Open Invention Network consortium, created to protect open-source technologies from patent lawsuits.
Additionally, the technology giant said Wednesday it would contribute more than 60,000 of its patents to the Open Invention Network. This is noteworthy because the group’s member companies cross-license their patents to each other to prevent future lawsuits in which companies may allege that another firm’s technology infringes on their own patents.
The OIN group formed in 2005 to protect proponents of the open source Linux operating system from legal actions, and now covers a broader range of open source technologies. Developers and companies can access and contribute to open source technology for free, unlike proprietary software like Microsoft’s (msft) Windows operating system.
“We know Microsoft’s decision to join OIN may be viewed as surprising to some; it is no secret that there has been friction in the past between Microsoft and the open source community over the issue of patents.” wrote Microsoft corporate vice president and deputy general counsel Erich Andersen in a blog post.
For years, Microsoft has waged legal battles against companies working on open source technologies like Linux and Google’s Android operating system, alleging that the open-source tech infringed on its own patents.
But as open source technologies have become more popular with developers and corporations in recent years, Microsoft has shifted its attitude towards the tech that it once considered a major threat to its business. As the company puts more resources into its Azure cloud computing service, it has been increasingly pushing into open source technologies as a way to court developers to build apps on Azure.
One of Microsoft’s first major steps to appease the open-source community occurred in 2014 when the company said it would open source its .NET developer framework. Red Hat CEO Jim Whitehurst told Fortune in 2016 that “Developers now are heavily using open-source tools and technology and, bluntly, I think that’s why Microsoft had to open source .NET and why they’re embracing more open source in general.”
Get Data Sheet, Fortune’s technology newsletter.
Microsoft’s latest big open source play is its decision to buy GitHub, an open-source friendly service for developers to store their software code, for $7.5 billion.
“Through its participation in OIN, Microsoft is explicitly acknowledging the importance of open source software to its future growth,” OIN CEO Keith Bergelt said in a statement.