BOLT BERANEK &lt;BBN> FILES FOR DEBENTURE OFFERING
  Bolt Beranek and Newman Inc said it
  filed with the Securities and Exchange Commission a
  registration statement covering a 75 mln dlr issue of
  convertible subordinated debentures due 2012.
      A portion of the proceeds will be used to acquire all of
  the outstanding capital stock of Network Switching Systems Inc.
   Another part will allow Bolt to exercise its option to
  purchase all of the limited partnership interests in BBN
  RS/Expert Limited Partnership, with the rest used for general
  corporate purposes. The company named PaineWebber, Merrill
  Lynch and Montgomery Securities as underwriters.
  

