PT Diagnostics [NPE] filed four separate suits against CAMP Systems, Hamilton Sundstrand, Pratt & Whitney Canada, Sikorsky Aircraft, and United Technologies, alleging that the defendants’ preventative airplane maintenance products and services infringe four patents related to analyzing data gathered from the operation of airplanes for preventative maintenance.  PT Diagnostics filed one prior suit against eight companies, including Honeywell, in November 2010.  The patents-in-suit originated with PT Holdings and were assigned PT Diagnostics in September 2010.  12/13, Eastern District of Texas, 2:2011cv00507; 2:2011cv00508; 2:2011cv00509; 2:2011cv00510.