By IAN AUSTEN
OTTAWA, Dec. 2 - What if your BlackBerry screen went dark?
To executives like Douglas M. Steenland of Northwest Airlines, the idea of doing business without a BlackBerry is about as appealing as reverting to rotary dial phones and Telex machines.
"It's the proverbial blessing and curse," Mr. Steenland said of his BlackBerry, which sends e-mail messages wirelessly. "It's a blessing because it liberates you from the office. It's a curse because there's no escape."
That is why there was so much anxiety throughout corporate America over this week's news that a long-running patent infringement battle between the maker of BlackBerry, Research In Motion, and NTP, a tiny patent holding company, might cause a service shutdown, perhaps within a month.
Indeed, the prospect of life without BlackBerries is so frightening to Northwest -- a heavy user if ever there was one -- that the airline immediately demanded a conference call with R.I.M. executives and one is scheduled for Tuesday.
"Everybody here hopes that somebody else will fix the problem," said Andrea F. Newman, Northwest's senior vice president for government relations. "But no one really knows what the problem is or what it will take to fix it."
R.I.M., which is based in Waterloo, Ontario, promises it has a solution that will keep its beloved BlackBerries humming even in the face of an injunction. While most analysts view the prospects of a shutdown as unlikely, they have little faith in the proposed solution, which has potential legal pitfalls of its own. What's more, the history of the struggle between the companies means that no outcome is certain. (R.I.M. declined to comment.)