none of those either

Author: Phil Sturgeon

versions/3.1.0.md

@@ -75,7 +75,7 @@ Path templating refers to the usage of template expressions, delimited by curly
 
 Each template expression in the path MUST correspond to a path parameter that is included in the [Path Item](#path-item-object) itself and/or in each of the Path Item's [Operations](#operation-object).
 
-The value for these path parameters MUST NOT contain unescaped forward slashes (`/`).
+The value for these path parameters MUST NOT contain any unescaped "generic syntax" characters described by [RFC3986](https://tools.ietf.org/html/rfc3986#section-3): forward slashes (`/`), forward question marks (`?`), or hashes (`#`).
 
 ##### <a name="mediaTypes"></a>Media Types
 Media type definitions are spread across several resources.