Re: The History of RP!

Date: Sat Sep 04 1999 - 17:25:55 EEST

In a message dated 99-09-03 20:08:41 EDT, ATiburon writes:

<< In a message dated 99-09-03 11:21:58 EDT, writes:
 << 4,575,330 Apparatus for production of three-dimensional objects by
  stereolithography Hull; Charles W., Arcadia, CA UVP, Inc., San
  Gabriel, CA
 That reminds me, isn't that patent about to expire? Possibly leading to some
comptition? I know there are more recent ancilliary patents though.
 Andy Scott
 Lockheed Martin Aero Sys

Hi Andy and Mick:

That patent issued on 3/11/86, and at the time the term of a patent was 17
years, putting the expiration at 2003. However, there was at least one
challenge to the patent by Dupont fairly early on, and I believe it resulted
in a modification of the claims. It may have also resulted in a change in
the term of the patent, but I haven't looked into it. The PTO's web site
copy doesn't indicate anything unusual about the term, although there's no
guarantee without further delving that there are no changes.

One thing I'm pretty sure of: Albert C. Young of Aaroflex will know; he may
even have a special clock.

The Japanese systems producers will also know. I remember the statement made
maybe 10 years ago to a US technology delegation that was written up in one
of their trip reports. (Can't remember exact details, but I think Dick Aubin
was one of the members.) The Japanese industry strategy was to compete
ferociously in the home market while making incremental improvements, and to
wait for the patents to expire in other markets.

While this patent is certainly one of 3D's crown jewel IP properties, they
have managed to build a wall of related IP - and presumably a war chest -
that offers them a broad array of offensive rights. I'm not a patent lawyer
and I don't even play one on TV, but it looks like a nice little mine field
to have surrounding you. I can't even tell what significant differences
exist between some of the patents when I hold matching pages up to a light.
This is also a strategy used by numerous Japanese and large US companies that
can afford it.

SLA Competition? I can give you a very definite maybe.


Ed Grenda
Castle Island Co.
19 Pondview Road
Arlington, MA 02474 USA
781-646-6280 (voice or fax) (email)

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