Markup Files 
Markup files (*.markup) contain
only markup data in the form of comments. You can choose to save markup
data as separate markup files, without the model or drawing file data,
which makes smaller-sized files.
Markup files are useful when you need several people to review a file.
For example, reviewers can add comments, then send you only a markup file.
You can open your version of the model, then open each individual markup
file to see the comments. The comments are opened on top of the model
and appear on the Markup tab in
the SolidWorks
eDrawings Manager.
Markup files have the following characteristics:
You must open the model or drawing file that the
markup data relates to before
you open the markup file itself.
If you add markup data to a model or drawing file,
and then open a previously created markup file (for that same model or
drawing file), the markup file data overwrites any comments in the model
or drawing file that have the same name.
If you want to save markup data in the model or
drawing file and in a markup file, you must save the files separately.
To create markup files:
Add comments
and associated markup
elements to a file.
Click Save Markup
(Markup tab
) or File, Save
Markup.
In the Select
Markup to Save dialog box, select individual reviewers or <All Reviewers>, and click OK.
In the Save As
dialog box, browse to a folder, verify the file name, and click Save.
To open markup files:
Open the eDrawings document that has a related
markup file.
Click File,
Open Markup.
Select a related markup file and click Open.
Select comments in the
Markup Comments
tree to display them in the graphics area.