premise: 4. The above restrictions shall not apply to Confidential Information which  (a) is in the public domain or is properly in the possession of the LHT without restriction at the time of receipt hereunder;  (b) subsequently enters the public domain without breach hereof by LHT;  (c) is lawfully received from a third party without restriction on disclosure;  (d) is independently developed by LHT's personnel who have not had direct or indirect access to or knowledge of the Confidential Information;  (e) is used or disclosed with the prior written approval of HPAC; and  (f) is obligated to be produced under order of a court of competent jurisdiction (provided that the LHT gives adequate notice of such pending order to HPAC so that HPAC can seek a protective order or other appropriate remedy). 