diff --git a/doc/src/write_data.rst b/doc/src/write_data.rst
index 13a6476ac4..0df3f7e4b2 100644
--- a/doc/src/write_data.rst
+++ b/doc/src/write_data.rst
@@ -42,16 +42,24 @@ Similar to :doc:`dump <dump>` files, the data filename can contain a "\*"
 wild-card character.  The "\*" is replaced with the current timestep
 value.
 
-.. note::
+.. admonition:: Data in Coeff sections
 
-   The write-data command is not yet fully implemented in two
-   respects.  First, most pair styles do not yet write their coefficient
-   information into the data file.  This means you will need to specify
-   that information in your input script that reads the data file, via
-   the :doc:`pair_coeff <pair_coeff>` command.  Second, a few of the :doc:`atom styles <atom_style>` (body, ellipsoid, line, tri) that store
-   auxiliary "bonus" information about aspherical particles, do not yet
-   write the bonus info into the data file.  Both these functionalities
-   will be added to the write_data command later.
+   The write_data command may not always write all coefficient settings
+   to the corresponding Coeff sections of the data file.  This can have
+   one of multiple reasons. 1) A few styles may be missing the code that
+   would writes those sections (if you come across one, please notify
+   the LAMMPS developers). 2) Some pair styles require a single pair_coeff
+   statement and those are not compatible with data files. 3) and finally
+   the default for write_data is to write a PairCoeff section, which has
+   only entries for atom types i == j. The remaining coefficients would
+   be inferred through the currently selected mixing rule.  If there has
+   been a pair_coeff command with i != j, this setting would be lost.
+   LAMMPS will detect this and print a warning message unless *pair ij*
+   is appended to the write_data command.  This will request writing a
+   PairIJCoeff section which has information for all pairs of atom types.
+   In cases where the coefficient data in the data file is incomplete,
+   you will need to re-specify that information in your input script
+   that reads the data file.
 
 Because a data file is in text format, if you use a data file written
 out by this command to restart a simulation, the initial state of the