Halloween documents are files that were supposedly confidential to Microsoft. The documents consisted of company memoranda, statements, and internal reports that generally discussed how Linux and open-source software competed against Microsoft and how the company should address them.

The Halloween documents were initially leaked in October 1998, with their sources unnamed. The documents were sent to Eric Raymond, a software developer and open-source software advocate, who immediately published them. In the years that followed, more confidential Microsoft documents were leaked from various sources, bringing the number to 11 documents to date.


Read More about Halloween Documents

Over the years, several Halloween documents have been released, but the topics often revolved around open-source software. Read on to learn more about Halloween documents.

Who Received the First Halloween Documents?

The first Halloween documents were leaked to Eric Raymond, a software developer who initially began his career developing proprietary software. In 1996, he helped develop an open-source email software called “Fetchmail.”

After this experience, Raymond began advocating for the development and adoption of open-source software. He wrote an essay entitled “The Cathedral and the Bazaar.” He turned this essay into a book in 1999.

Why Refer to the Documents as Halloween Documents?

Raymond received the first batch of confidential Microsoft documents in the last week of October 1998, around Halloween. He received them a year or so after presenting his essay “The Cathedral and the Bazaar” at the Linux Kongress in Germany. 

Many subsequent documents were also released around the same time in different years. 

What Are the Halloween Documents?

There are 11 Halloween documents in total. They are briefly described below, but their complete content can be found here.

  • Halloween I: An internal report that provides insights into how Microsoft sees open-source software as a threat. The report was entitled “Open-Source Software: A (New?) Development Methodology.” Raymond believed the document was unintentionally leaked.
  • Halloween II: Another leaked internal report that is a follow-up to the first document. The document’s title was “Linux OS Competitive Analysis: The Next Java VM?” It contains an evaluation of Linux in terms of performance, reliability, market share, and other competitive aspects. The report was sent to Raymond a few days after he published Halloween I.
  • Halloween III: A statement released by Microsoft in response to the leakage of the Halloween documents, where it confirmed the authenticity of Halloween I.
  • Halloween IV: Raymond wrote “When Software Things Were Rotten” as a response when a Microsoft executive referred to open-source developers as Robin Hood.
  • Halloween V: Another article written by Raymond to address the statement made by a Microsoft executive about Linux’s “weak value proposition.”
  • Halloween VI: A piece written by Raymond to recount the changes that happened in Linux and the open-source community a year after the Halloween documents were first leaked. Entitled “The Fatal Anniversary,” the article also talked about research studies conducted by Gartner for Microsoft.
  • Halloween VII: A Microsoft memo called “Research E-Bulletin: Attitudes toward Shared Source and Open-Source Research Study” that was presented during an internal Linux Strategic Review in 2002. In the report, Microsoft researchers detailed market reactions to the company’s Shared Source Initiative.
  • Halloween VIII: A leaked email from a Microsoft executive with the subject line “OSS and Government” urging the company to be more prepared to respond to announcements and news about governments and large organizations shifting to open-source software.
  • Halloween IX: A document written by Raymond in response to the SCO Group, Inc. v. IBM case where the former accused IBM of breach of contract and copyright infringement, among others.
  • Halloween X: A leaked email from a consultant to an SCO executive revealing Microsoft’s alleged payoff to the company.
  • Halloween XI: “Entitled Get the FUD,” this document was Raymond’s response to Microsoft’s “Get the Facts” movement. 

The Halloween documents revealed that Microsoft sees open-source software development as a threat. It also shows the company studied Linux thoroughly. The last document was published in 2004. Many things have changed since then, including Microsoft’s acceptance and contribution to the open-source community.

Key Takeaways

  • The Halloween documents refer to a series of documents that highlight Microsoft’s view of open-source software development.
  • The leakage of the Halloween documents began in 1998 when an internal Microsoft memo about how open-source software threatened the company’s revenue.
  • The documents were leaked close to Halloween, hence their name.
  • The Halloween documents contain several confidential memos, internal reports, and Raymond’s responses to Microsoft statements.
  • Raymond is a software developer and open-source software advocate.
  • There are 11 Halloween documents.
  • Halloween I was believed to have been unintentionally leaked, but a former Microsoft employee sent Halloween II to Raymond on purpose.