0.  emacs -Q
1.  Eval: (put 'upcase-region 'disabled nil)
          (put 'downcase-region 'disabled nil)
2.  Visit the attached file.
3.  Move point to just after the comma.
4.  Define a *rectanguar* region: C-x <SPC> C-n C-e
5.  Downcase the rectangular region: C-x C-l
6.  Repeat steps #3 to #5, but this time for upcasing the region
    instead of downcasing it ('C-x C-u' instead of 'C-x C-l').

The upcased text in the last step is not only the one marked by the
rectangular region.  The upcasing command acts as if a linear
(i.e. non-rectangular) region was active at that moment.



In GNU Emacs 25.0.92.1 (i686-pc-mingw32)
 of 2016-04-22 built on LEG570
Repository revision: 2b31a0c21e51d39a82572a32d2d31b5a2aa174a3
Windowing system distributor 'Microsoft Corp.', version 6.1.7601
Configured using:
 'configure --host=i686-pc-mingw32'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS

Important settings:
  value of $LANG: ESN
  locale-coding-system: cp1252


-- 
Dani Moncayo