not sure what you mean by cisco/lucent since cisco doesn't appear in the history of LU
https://en.wikipedia.org/wiki/Lucent
Lucent Technologies, Inc., was an American multinational telecommunications equipment company headquartered in Murray Hill, New Jersey, in the United States. It was established on September 30, 1996, through the divestiture of the former AT&T Technologies business unit of AT&T Corporation, which included Western Electric and Bell Labs.[1]
Lucent was merged with Alcatel SA of France on December 1, 2006, forming Alcatel-Lucent.[2] Alcatel-Lucent was absorbed by Nokia in January 2016.
so in theory whatever basis you had in LU became the basis in the Nokia shares you received in the merger.
Nokia is still traded on the NYSE
if the company value sinks even to the point where it's a fraction of a cent on the pink sheets, the IRS says it's not worthless and you can't write it off until you sell.
the same would be true for cisco. even if the value dropped by 99.99% from what you paid. until you sell the IRS says you are not entitled to a loss deduction.
cisco is traded on the NASDAQ and as of 12/24/2020 had a value in excess of $40/share.
