1 Kendall Square #143
P.O.Box 9171
Cambridge, Massachusetts 02139


Richard Stallman, (617) 253-8830

	Programmer obtained AT&T software patent being used to threaten MIT,
	gives talk at MIT and is picketed by programmers.

CAMBRIDGE, MA, November 18, 1991 -- Rob Pike, a software designer from
AT&T Bell Labs, expected to deliver an ordinary seminar on his latest
research project.  Instead, he found a room filled with programmers
carrying signs to protest the consequences of his previous project:
the AT&T "backing store" patent which AT&T has used to threaten all
the members of the X Consortium, including MIT itself.

Of the approximately 80 people present at the talk, about 50 carried
protest signs.  The protestors did not try to interfere with the
seminar.  They simply raised their signs as Pike began to speak.  This
accomplished the purpose of making their ire known.

"Backing store" refers to a technique used in window systems.  When
part of a window is covered by other windows, the hidden pixels are
copied elsewhere in memory, off of the screen.  When the obscured part
becomes visible again, the pixels are copied back onto the screen.  In
the meantime, all output to the window is written partly on the screen
and partly in the off-screen memory.  The term "backing store" refers
to the memory used to hold the pixels when they are not on the screen.

The X Window system was developed by MIT Project Athena in the 1980s,
and now used by most workstation vendors.  It is now maintained by the
X Consortium, an organization whose members include most workstation
vendors.  The X Window system has implemented backing store since a
couple of years ago.

Software developers at Bell Labs have described this technique as "an
invention", and asserted that it was copied by MIT.  However, most
programmers would say that the idea is an obvious one, and MIT does
not acknowledge Pike's work as its inspiration.  (The question of how
the X Window developers came by the idea of backing store would have
no effect on the outcome of a lawsuit, since patents prohibit the use
of a technique even if one has developed it independently.)

Pike filed an application for a patent on the backing store technique
on October 7, 1982, after developing a window system for the AT&T
"BLT" terminal which used the technique.  Patent number 4,555,775 was
issued on November 26, 1985.

AT&T made its threat against the X Consortium members by letters in
February 1991 asserting that use of the X Window system requires a
license from AT&T.  While these letters did not state an intention to
sue, the possibility of litigation as the next step was implicit.

On September 24, 1991, the X Consortium stated its position on the matter,
asserting that 

    ... The recent proliferation of software patents is creating
    pressure on software developers to seek patent protection for
    straightforward ideas, and increasing pressure to claim broad
    applicability of software patents, well beyond the scope of any
    original invention.  These practices introduce a chilling effect
    on university research, and they undermine our ability to pursue
    ideas in a free and open climate. ...

Reportedly, MIT is preparing a press release on the matter, and
will complete it whenever journalists begin calling to ask for copies
of it.  To contact MIT, call (617) 253-1000.

The demonstration was planned three days earlier by Richard Stallman
after he noticed signs announcing the seminar.  Stallman is one of the
founders of the League for Programming Freedom, a grassroots
organization whose purpose is to defend programmers' freedom to write
software.  The League opposes the application of patents to software
because this threatens the freedom of programmers.

Prominent members of the League include:

John McCarthy, Professor at Stanford.  Inventor of Lisp.

Marvin Minsky, Professor at MIT.  One of the founders of artificial

Rod Brooks, Professor at MIT.  Known for work on microrobots.

Robert Boyer, Professor at University of Texas.
	Known for Boyer-Moore string search.
	Co-founder of Computational Logic, Inc.

Patrick Winston, Director, MIT Artificial Intelligence Lab.
	Also associated with Ascent Technology.

Gerry Sussman, Professor at MIT.
	Author of "Structure and Interpretation of Computer Programs".

Harold Abelson, Professor at MIT.
	Author of "Structure and Interpretation of Computer Programs".

Richard Stallman, President, Free Software Foundation.

William A. Wulf, Professor at University of Virginia.
	Former assistant director of NSF.  IEEE and AAAS Fellow.

Stan Kugell, founder of Javelin Software.  Javelin received Product
	of the Year awards from InfoWorld and European Business Software.
	(Currently President of Fairfield Software Corp.)

Les Earnest, founder and first president of Imagen, and author of
	the first spelling checker.

Richard P. Gabriel, founder and first president of Lucid.
	(Currently Chief Technical Officer.)

Peter Deutsch, Chief Scientist, Parc Place Systems.

Guy Steele, Senior Scientist, Thinking Machines Corp.

William Madison, author of Skyhawk PC utilities and ReadyRef.
	Former director of software devel at Harvard Bus. Schl.
	Former chairman of ANSI X3 Standrds Planning and Requirements Comm.

For further information about the League, write: League for
Programming Freedom, 1 Kendall Square #143, PO Box 9171, Cambridge, MA
02139.  Or phone (617) 243-4091.

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Note to editors: position papers and other background information
available upon request.