http://gnuwin32.sourceforge.net/packages/wget.htm
Using wget (above) or whatever, load the html you get from:
http://emma.msrb.org/SecurityView/SecurityDetails.aspx?cusip=581225AF6
(your example doc number was used above)
Search results for this text:
_ctl02_documentHyperLink" href="
and take all text to the next "
/MS204365-MS179673-MD348245.pdf
Merge the string with the domain:
http://emma.msrb.org
wget the result
http://emma.msrb.org/MS204365-MS179673-MD348245.pdf
After that, you'll find tons of code snippets on the web under the description of "PDF2TXT" to complete the job and arrive at some output.
BTW, if you are thinking of frequent access, you should first ask for permission from the site. (if you use wget, don't forget the 4 dependency dll's)