diff --git a/STYLE_GUIDE.md b/STYLE_GUIDE.md
index ac6b9b7..64d776e 100644
--- a/STYLE_GUIDE.md
+++ b/STYLE_GUIDE.md
@@ -1,9 +1,9 @@
-# Style Guide for MDAnalysis
+# Style Guide for MDAnalysis<sup>®</sup>
 
 ## Name
 When referring to the project we always capitalize as 
 
-* ✔️ MDAnalysis
+* ✔️ MDAnalysis<sup>®</sup>
 
 and _not_
 * ✖️ ~~MDanalysis~~
@@ -14,10 +14,10 @@ and _not_
 In logo art we _may_ break the name as
 
  MD<br/>
- Analysis
+ Analysis<sub>®</sub>
 
 
-*MDAnalysis* is a proper noun when we refer to the project/organization or the library itself so it is typeset in the standard typeface of the surrounding text. It is _not_ set in `monospace` typeface.  It _may_ be set in italics (*MDAnalysis*) or another common style (e.g., sans serif) to visually distinguish software names.
+*MDAnalysis®* is a proper noun when we refer to the project/organization or the library itself so it is typeset in the standard typeface of the surrounding text. It is _not_ set in `monospace` typeface.  It _may_ be set in italics (*MDAnalysis*) or another common style (e.g., sans serif) to visually distinguish software names.
 
 * ✔️ MDAnalysis
 * ✔️ *MDAnalysis*
@@ -30,6 +30,8 @@ If we refer to the importable Python package of the MDAnalysis library or if we
 * ✔️ "Importing the `MDAnalysis` package is a form of linking as far as the GPL is concerned."
 * ✖️ ~~"When loading the MDAnalysis package you can alias it to the short form mda."~~
 
+MDAnalysis<sup>®</sup> is a *registered trademark* in the US and elsewhere. See [Trademark](#trademark) below for details on how to use the ® symbol.
+
 ## Colors
 ### Logo Colors
 
@@ -65,3 +67,32 @@ The [User Guide CSS theme](https://github.com/MDAnalysis/UserGuide/blob/develop/
 
 * The MDAnalysis logo typeface is "ZAG Bold" from https://www.dafont.com/de/zag.font (see MDAnalysis/UserGuide#11).
 * We generally prefer sans serif fonts for our materials (Helvetica, Arial)
+
+## Trademark
+
+The ® symbol may only be used for federally registered trademarks. MDAnalysis is a registered trademark of NumFOCUS, Inc., so we are allowed to use it.
+
+The ® symbol should be added wherever possible when referring to the project name or logo.
+This includes:
+- The project name in text
+- The project logo
+- Documentation, websites, and presentations where the mark appears
+
+### Where to place the ® symbol
+The ® symbol usually appears only with the first or most prominent mention of the trademark in a document or page.
+
+General guidance:
+- Text: place the ® as a superscript to the upper right of the name
+- Logos: place the ® as a subscript to the lower right of the logo
+
+In our logo, the symbol should appear at the lower right of the logo.
+
+### Branding and style choices
+There are no strict legal rules about the exact size or styling of the ® symbol. We can decide how it should appear in our branding.
+
+Common practices include:
+- Showing the ® symbol the first time the logo or name appears
+- Making sure the symbol is large enough to be visible
+- Including guidance in your branding documentation so others know how to display it correctly
+
+For more information see [this guide](https://www.mekiplaw.com/trademark-symbols-explained/).