united states securities and exchange commission washington dc 20549 form 10 k mark one 5 annual report pursuant to section 13 or 15 d of the act 1934 for fiscal year ended december 31 2005 transition file number 1 5083 xanser corporation exact name registrant as specified in its charter delaware 74 1191271 state other jurisdiction incorporation organization irs employer identification no 2435 north central expressway richardson texas 75080 address principal executive offices zip code s telephone including area 972 699 4000 registered 12 b title each class on which common stock without par value new york 8 3 4 convertible subordinated debentures due 2008 g none indicate by check if is a well known seasoned issuer defined rule 405 yes not required