diff --git a/sdf/1.3/root.sdf b/sdf/1.3/root.sdf
index ac4adff4c..27a20b8b9 100644
--- a/sdf/1.3/root.sdf
+++ b/sdf/1.3/root.sdf
@@ -2,7 +2,15 @@
SDFormat base element.
- Version number of the SDFormat specification.
+
+ Version number of the SDFormat specification, consisting of major
+ and minor versions delimited by a `.` character.
+ A major version bump is required if older versions cannot be
+ automatically converted to this version.
+ A minor version bump is required when there are breaking changes that
+ can be handled by the automatic conversion functionality encoded in the
+ `*.convert` files.
+
diff --git a/sdf/1.4/root.sdf b/sdf/1.4/root.sdf
index 429de91b9..563dd1e90 100644
--- a/sdf/1.4/root.sdf
+++ b/sdf/1.4/root.sdf
@@ -2,7 +2,15 @@
SDFormat base element.
- Version number of the SDFormat specification.
+
+ Version number of the SDFormat specification, consisting of major
+ and minor versions delimited by a `.` character.
+ A major version bump is required if older versions cannot be
+ automatically converted to this version.
+ A minor version bump is required when there are breaking changes that
+ can be handled by the automatic conversion functionality encoded in the
+ `*.convert` files.
+
diff --git a/sdf/1.5/root.sdf b/sdf/1.5/root.sdf
index ac5d10bb6..b69bdf99c 100644
--- a/sdf/1.5/root.sdf
+++ b/sdf/1.5/root.sdf
@@ -2,7 +2,15 @@
SDFormat base element.
- Version number of the SDFormat specification.
+
+ Version number of the SDFormat specification, consisting of major
+ and minor versions delimited by a `.` character.
+ A major version bump is required if older versions cannot be
+ automatically converted to this version.
+ A minor version bump is required when there are breaking changes that
+ can be handled by the automatic conversion functionality encoded in the
+ `*.convert` files.
+
diff --git a/sdf/1.6/root.sdf b/sdf/1.6/root.sdf
index 3c2a3a396..afecf0d00 100644
--- a/sdf/1.6/root.sdf
+++ b/sdf/1.6/root.sdf
@@ -2,7 +2,15 @@
SDFormat base element that can include 0-N models, actors, lights, and/or worlds. A user of multiple worlds could run parallel instances of simulation, or offer selection of a world at runtime.
- Version number of the SDFormat specification.
+
+ Version number of the SDFormat specification, consisting of major
+ and minor versions delimited by a `.` character.
+ A major version bump is required if older versions cannot be
+ automatically converted to this version.
+ A minor version bump is required when there are breaking changes that
+ can be handled by the automatic conversion functionality encoded in the
+ `*.convert` files.
+
diff --git a/sdf/1.7/root.sdf b/sdf/1.7/root.sdf
index 76ab2881c..d5c9f62e0 100644
--- a/sdf/1.7/root.sdf
+++ b/sdf/1.7/root.sdf
@@ -2,7 +2,15 @@
SDFormat base element that can include 0-N models, actors, lights, and/or worlds. A user of multiple worlds could run parallel instances of simulation, or offer selection of a world at runtime.
- Version number of the SDFormat specification.
+
+ Version number of the SDFormat specification, consisting of major
+ and minor versions delimited by a `.` character.
+ A major version bump is required if older versions cannot be
+ automatically converted to this version.
+ A minor version bump is required when there are breaking changes that
+ can be handled by the automatic conversion functionality encoded in the
+ `*.convert` files.
+