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Built on day one. Rebuilt for today.

1999
Brent Rector starts writing Demeanor against internal Microsoft "Lightning" builds — before Microsoft publicly announces .NET.
June 2000
Wise Owl announces Demeanor and ships the first beta alongside .NET Beta 1. The first .NET obfuscator.
Feb 2002
.NET Framework 1.0 ships. Demeanor is already a mature, production-shipping product on day one.
2003–2020
Wise Owl keeps Demeanor current through every .NET generation. Red Gate Software — a long-time Demeanor customer — approaches Wise Owl about acquiring Demeanor for their developer-tools portfolio. Wise Owl's founder, appreciating the vote of confidence, declines the offer. Red Gate then buys SmartAssembly as their alternative.
2021
Brent rips out per-seat phone-home licensing and replaces it with per-company self-validating keys — no activation server, no machine locking, no seat counting.
2025–26
Brent ships the complete ground-up rewrite. Modern C# 14, .NET 10, one NuGet package with Windows, Linux, and Mac binaries.

One product. One vendor. One engineering hand. 27 years.

Other products in this market change hands — acquired, rolled into private-equity brand umbrellas, handed off to new owners, transitioned from free to paid mid-life, or left dormant for years at a stretch. Demeanor has done none of those things. It is the original .NET obfuscator, and it is still owned, maintained, and shipped by the same engineer who began writing it in 1999 against Microsoft's internal “Lightning” .NET alpha builds — and shipped its first public beta alongside .NET Beta 1 in June 2000.

Demeanor for .NET
1999 → today
  • Owner: Wise Owl Software (unchanged)
  • Developer: Brent Rector (original, unchanged)
  • Acquisitions: None
  • Brand changes: None
  • Free-to-paid transitions: None
  • Dormant periods: None
Dotfuscator (PreEmptive)
2003 → today
  • Acquired by Idera, March 2021
  • Rolled into Sembi brand umbrella, January 2025
  • Now sits three corporate layers above the customer
SmartAssembly
2005 → today
  • Independent studio until 2010–2011
  • Acquired by Red Gate Software
  • Not listed among Red Gate's strategic products in 2026
Eazfuscator.NET
2008 → today
  • Free personal project, 2008–2012
  • Commercialized under Gapotchenko in 2012
  • Free-to-paid transition mid-lifecycle

For a buyer whose procurement window extends past the next vendor acquisition cycle — i.e. someone who wants the vendor on their PO today to still exist, unchanged, when they sign a renewal in 2030 — continuity of ownership is a signal worth reading. It is the cleanest commercial-continuity record in this market and it is not one any other commercial .NET obfuscator can match.

Brent Rector

Photo of Brent Rector, author of Demeanor for .NET

Brent Rector wrote Demeanor, the original .NET obfuscator, and has shipped it continuously under the Wise Owl Software name for twenty-seven years.

Brent’s career spans five decades — mainframes, minis, PCs, cloud, and AI. Nearly twenty of those years sit inside Microsoft as a Principal Software Architect: a decade on Windows itself, then a decade on Visual Studio, the Windows SDK, and .NET. When you buy Demeanor you are buying a tool whose author helped build the platform it runs on and the developer tools you use to build against that platform.

Brent also authored multiple Microsoft Press titles on Windows internals and served as an early Microsoft Regional Director. He runs Wise Owl Software out of San Diego, California.

Demeanor v6 is a complete ground-up rewrite in modern C# 14 targeting .NET 10. The v6 release introduces the pre-obfuscation audit — the feature that separates Demeanor from every other .NET obfuscator on the market. Analyze the code first. Tell the developer what will break and how to fix it. Then, and only then, rewrite the assembly.

Know what breaks before you obfuscate.

27 years of .NET obfuscation experience, distilled into a tool that analyzes first and rewrites second. One NuGet package. One MSBuild property. Zero surprises at runtime.

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