Re: lzw patent search
If I distribute an application over the Internet, it is my understanding
that I have to wait for the LZW patent to expire in all countries or
potentially be doing something illegal. If that is the case, then knowing
when the Canadian patent expires only helps if I'm selling a product in
Canada and restricting its export. I would like to know when the last
basic LZW patent expires and what agreements for the international
distribution of the LZW algorithm might be available.
What Unisys patents/pending patents might cover the version of LZW that is
used in the GIF file format, and/or Unix Compress?
On Mon, 10 Mar 2003 email@example.com wrote:
> In Canada, the basic LZW patent expires July 7, 2004. Be advised that Unisys
> has many patents issued and pending on variants from basic LZW.
> From: Drew Scott Daniels <umdanie8@cc.UManitoba.CA> on 03/07/2003 03:14 PM
> To: LZW_INFO@UNISYS.COM@SMTP@ExchangeUSBBGW
> cc: firstname.lastname@example.org@SMTP@ExchangeUSBBGW
> Subject: lzw patent search
> When do all the lzw related patents expire? I've heard different stories
> and am confused by all the different patents that seem to exist for lzw.
> I also am unsure as to how to search for information about each of the lzw
> including United States Patent No. 4,558,302, Japanese Patent Numbers
> 2,123,602 and 2,610,084, and patents in Canada, France, Germany, Italy and
> the United Kingdom.
> Welch Patent Licensing Department; Unisys Corporation; Mail Stop E8-114;
> Unisys Way, Blue Bell, PA 19424. Via the Internet, send E-mail to
> LZW_INFO@UNISYS.COM. Via facsimile, send inquiries to Welch
> Patent Licensing Department at 215-986-3090
> Drew Daniels