Hmm . . . I'm not sure I understand this point of
view. Katz _stole_ the
algorithm from ARC -- why shouldn't they sue?
"Stole" the algorithm? Unless they had a patent on it, which AFAIK
they didn't, it's not intellectual property to steal. (Under US law,
at least.) On what grounds would they have a basis to sue?
The actual issue was that they claimed to have a trademark on the use
of "ARC" as a file extension. Despite the fact that there were known
cases of that extension being used by other software before SEA's program
was even written.
My understanding is that P.K. decided to choose another name rather than
fighting SEA.
I was using ARC and PKZIP extensively back in
'88-'89 and IIRC Katz
reverse-engineered the ARC code in order to make his product work.
Which was legal, and would still be legal now (the DMCA notwithstanding).
If this happened to me I would lose my sense of humor
very quickly . . .
If this happened to me I'd work hard to make sure that my product
offered a sufficiently good value proposition to the customer that
it kept selling. If a product fails to do that, it *deserves* to
be consigned to oblivion. Just because your product was selling well
at some point at the past doesn't imply any god-given right or
entitlement that it should continue to do so in the future with no
further effort on your part.