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Posted to users@spamassassin.apache.org by John Levine <jo...@taugh.com> on 2011/03/01 04:20:49 UTC

Re: Should Emails Have An Expiration Date

>I do like the idea with respect to alerts; if email programs (especially
>those on smart phones) would know to avoid alerting you of unread +
>expired messages, that could be quite beneficial.  Especially if I could
>set expiration times with thunderbird filters.

If people keep at it, they may yet reinvent RSS which, I note, T'bird
supports reasonably well.

The main appeal of Expires: is to spammers and near-spammers, who hope
they can make the mail go away before people complain about it.  As I
pointed out to Ken Magill, usenet has had an Expires: header for
decades, the design of usenet makes it cheap to implement, and it has
never been useful in practice.


Re: Should Emails Have An Expiration Date

Posted by Martin Gregorie <ma...@gregorie.org>.
On Wed, 2011-03-02 at 02:13 -0800, Ted Mittelstaedt wrote:
> On 3/1/2011 1:41 AM, Per Jessen wrote:
> > As well as anyone keeping
> > email-archives (e.g. for legals reasons).
> >
> 
> archiving is also specifically spelled out in the 1996 treaty as
> allowed.
> 
So, on that reading keeping an archival copy is OK under all legal
regimes provided that copies in all other mailboxes are expired on the
expiry date? 

And if, after that date, a copy is retrieved from the archive and placed
in a mailbox for later perusal by the person who asked to see it? Is it
meant to vanish immediately its been retrieved before it can be read?
  

Martin



Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/1/2011 1:41 AM, Per Jessen wrote:
> Ted Mittelstaedt wrote:
>
>>    From a legal perspective I will point out that any e-mail you
>> receive is (at least in the US, but most other countries too)
>> considered copyrighted by the sender.  Under copyright law the
>> sender has the right to control expiration of content they create,
>> the movie houses are doing this with digital copies that are
>> time-limited and included with blue-ray disc purchases.  Thus if
>> a corporation suddenly has e-mail disappearing from it's servers
>> due to expiration dates inserted by the e-mail creator they are
>> absolutely protected from a legal point of view - because of the
>> demands of copyright law.
>
> I guess this means places like gmane.org and marc.info are in gross
> violation of all kinds of copyrights.

no, because fair use is defined in copyright.  those are fair use.

> As well as anyone keeping
> email-archives (e.g. for legals reasons).
>

archiving is also specifically spelled out in the 1996 treaty as
allowed.

> Regardless, copyright is not the same everywhere.  Far from it. The
> Urheberrecht in e.g. Germany and Switzerland is quite different.  I
> doubt if anyone here would be able to claim Urheberrecht for an email.
>

Any country that is signatory to the 1996 WIPO treaty and the Berne
Convention is required by those to adjust their national laws to
match those treaties.  Most countries are signatories and most have
done so.  So yes, copyright IS mostly the same everywhere.  There
are some differences but they are not as significant as you think.

Ted

>
> /Per Jessen, Zürich
>
>


Re: Should Emails Have An Expiration Date

Posted by Per Jessen <pe...@computer.org>.
Ted Mittelstaedt wrote:

>  From a legal perspective I will point out that any e-mail you
> receive is (at least in the US, but most other countries too)
> considered copyrighted by the sender.  Under copyright law the
> sender has the right to control expiration of content they create,
> the movie houses are doing this with digital copies that are
> time-limited and included with blue-ray disc purchases.  Thus if
> a corporation suddenly has e-mail disappearing from it's servers
> due to expiration dates inserted by the e-mail creator they are
> absolutely protected from a legal point of view - because of the
> demands of copyright law.

I guess this means places like gmane.org and marc.info are in gross
violation of all kinds of copyrights.  As well as anyone keeping
email-archives (e.g. for legals reasons).

Regardless, copyright is not the same everywhere.  Far from it. The
Urheberrecht in e.g. Germany and Switzerland is quite different.  I
doubt if anyone here would be able to claim Urheberrecht for an email. 


/Per Jessen, Zürich


Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/1/2011 11:11 PM, Patrick Ben Koetter wrote:
> * Ted Mittelstaedt<te...@ipinc.net>:
>> On 3/1/2011 11:55 AM, John Levine wrote:
>>>>  From a legal perspective I will point out that any e-mail you
>>>> receive is (at least in the US, but most other countries too)
>>>> considered copyrighted by the sender.  Under copyright law the
>>>> sender has the right to control expiration of content they create,
>
> German law will not work in this case for the same reason it won't for email
> disclaimers too. The rationale is that "one-sided agreements rescind a
> contract", which is the case if a sender declares e.g. a copyright on a
> message

It's actually a lot more complex than that.

For starters, by definition copyright is automatic on any created 
content.  See the Berne Convention.  Germany signed that in 1887. 
Application of copyright wouldn't be considered a one-sided agreement. 
I suspect your confusing this with the so-called "shrink-wrap licenses"

 > or wants "to control expiration of content they create".
 >

This is a lot more complicated.

Keep in mind that e-mail is an electronic work and those have
more extensive copyright.  This was defined in the 1996
WIPO copyright treaty (that was mainly created to cover electronic
forms of content distribution) that is here:

http://www.wipo.int/treaties/en/ip/wct/trtdocs_wo033.html

In particular I will bring up the following section of the
treaty

Article 12
Obligations concerning Rights Management Information

(1) Contracting Parties shall provide adequate and effective legal 
remedies against any person knowingly performing any of the following 
acts knowing, or with respect to civil remedies having reasonable 
grounds to know, that it will induce, enable, facilitate or conceal an 
infringement of any right covered by this Treaty or the Berne Convention:

(i) to remove or alter any electronic rights management information 
without authority


The question is, is an "Expiration:" header part of electronic
rights management?  I think it would be very hard to argue that it
is not.

> It might have worked back in the days of half-way covenants
> <http://en.wikipedia.org/wiki/Half-Way_Covenant>  ... ;)
>

   If your system was programmed to expire the
mail as a result of the expiration and the content creator knew this
and wanted to take advantage of it by putting in an expiration,
then if you filtered the expiration out or otherwise defeated it,
you would be removing the rights management information.

In the US the 1996 WIPO treaty is implemented by the Digital
Millennium Copyright Act  (yet another instance where Congress
signed away more of our Constitutional rights)  I don't know
about Germany, but the treaty requires signatories to implement
it in their legal framework.

Ted

> p@rick
>
>
>
>
>>>
>>> I really think it would be a good idea for people to refrain from
>>> playing Junior Lawyer here.
>>>
>>> I know just enough about copyright law to know that this claim is
>>> nonsense.
>>>
>>
>> No, it is not nonsense.  Copyright law does allow the content creator
>> to specify duration of use.  If you go view a movie in a movie theater
>> you buy a ticket for a single viewing, you do not automatically get
>> to view it multiple times just because you bought a ticket.
>>
>> Ted
>>
>>> R's,
>>> John
>>
>


Re: Should Emails Have An Expiration Date

Posted by Mariusz Kruk <Ma...@epsilon.eu.org>.
On Wednesday 02 of March 2011, Ted Mittelstaedt wrote:
> >>> Furthermore, many copyright laws have "permitted use"
> >>> (sorry, don't know the right english term for it) instead of fair use
> >>> which explicitly says what can be done with a work after its first
> >>> publishing. And this use cannot be limited by any contract,
> >> Untrue when it comes to electronic works, as a result of WIPO Copyright
> >> 1996.
> > True.
> > For example, polish Office of Competition and Consumer Protection ruled
> > in 2007 that stamping "any form of copying or distribution" on CD's is
> > illegal because it misleads consumers into believing they don't have the
> > rights I mentioned above and forced the producer to change said notice
> > to the one corresponding to polish copyright law.
> > 
> > http://decyzje.uokik.gov.pl/dec_prez.nsf/0/2DEDF4B2AF9B7717C12574F6002AD7
> > E4?OpenDocument (sorry, polish only).
> 
> Still untrue.  As I said, electronic works.  A CD is treated
> in just about every country as a phonograph recording, not an
> electronic work.

What if I rip said CD to mp3? What if I send this mp3 to a friend via email?
It's perfectly legal for me to do both those things.

> We are in the midst of a time when people's right to use
> copyrighted material is being curtailed and the general public
> is just sucking it down like candy and hasn't a clue.

Unfortunately I have to agree here.


-- 
d'`'`'`'`'`'`'`'`'`'`'`'`'Yb 
`b  Kruk@epsilon.eu.org   d' 
d' http://epsilon.eu.org/ Yb 
`b,-,.,-,.,-,.,-,.,-,.,-,.d' 

Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/2/2011 2:31 AM, Mariusz Kruk wrote:
> On Wednesday 02 of March 2011, Ted Mittelstaedt wrote:
>>> Furthermore, many copyright laws have "permitted use"
>>> (sorry, don't know the right english term for it) instead of fair use
>>> which explicitly says what can be done with a work after its first
>>> publishing. And this use cannot be limited by any contract,
>> Untrue when it comes to electronic works, as a result of WIPO Copyright
>> 1996.
>
> True.
> For example, polish Office of Competition and Consumer Protection ruled in
> 2007 that stamping "any form of copying or distribution" on CD's is illegal
> because it misleads consumers into believing they don't have the rights I
> mentioned above and forced the producer to change said notice to the one
> corresponding to polish copyright law.
>
> http://decyzje.uokik.gov.pl/dec_prez.nsf/0/2DEDF4B2AF9B7717C12574F6002AD7E4?OpenDocument
> (sorry, polish only).
>

Still untrue.  As I said, electronic works.  A CD is treated
in just about every country as a phonograph recording, not an
electronic work.  And if you read the treaties (it's easy they
aren't long) it's clear what the intent is.  WIPO '96 is basically
a subtle plan to greatly extend copyright rights.  Even in 1996
they realized that non-electronic content distribution was
going to be replaced by electronic distribution.  So they
loaded a lot of new use restrictions into the electronic
content, because they understood that as time passed it would
expand copyright rights for more and more creations.

How long do you think that CD's are going to last?  In a
lot of audio forums they aren't giving them more than a decade
before they are mostly gone and it will all be itunes and
such.  Why do you think the book publishers are pushing
kindles and such?

We are in the midst of a time when people's right to use
copyrighted material is being curtailed and the general public
is just sucking it down like candy and hasn't a clue.

People think that Apple is some sort of white knight for
"forcing" the music publishers into using itunes, I laughed
my ass off the first time I read that.  Apple?  One of the
biggest proponents of the "we are going to control everything"
mentality?  They worship copyright.  Far from being forced,
the music publishers chose Apple because of this mentality.

Ted


Re: Should Emails Have An Expiration Date

Posted by Mariusz Kruk <Ma...@epsilon.eu.org>.
On Wednesday 02 of March 2011, Ted Mittelstaedt wrote:
> > Furthermore, many copyright laws have "permitted use"
> > (sorry, don't know the right english term for it) instead of fair use
> > which explicitly says what can be done with a work after its first
> > publishing. And this use cannot be limited by any contract,
> Untrue when it comes to electronic works, as a result of WIPO Copyright
> 1996.

True.
For example, polish Office of Competition and Consumer Protection ruled in 
2007 that stamping "any form of copying or distribution" on CD's is illegal 
because it misleads consumers into believing they don't have the rights I 
mentioned above and forced the producer to change said notice to the one 
corresponding to polish copyright law.

http://decyzje.uokik.gov.pl/dec_prez.nsf/0/2DEDF4B2AF9B7717C12574F6002AD7E4?OpenDocument
(sorry, polish only).

-- 
[------------------------] 
[  Kruk@epsilon.eu.org   ] 
[ http://epsilon.eu.org/ ] 
[------------------------] 

Re: Should Emails Have An Expiration Date

Posted by Per Jessen <pe...@computer.org>.
Ted Mittelstaedt wrote:

> On 3/2/2011 12:19 AM, Mariusz Kruk wrote:
>> On Wednesday 02 of March 2011, Patrick Ben Koetter wrote:
>>>>>>  From a legal perspective I will point out that any e-mail you
>>>>>>
>>>>>> receive is (at least in the US, but most other countries too)
>>>>>> considered copyrighted by the sender.  Under copyright law the
>>>>>> sender has the right to control expiration of content they
>>>>>> create,
>>> German law will not work in this case for the same reason it won't
>>> for email disclaimers too. The rationale is that "one-sided
>>> agreements rescind a contract", which is the case if a sender
>>> declares e.g. a copyright on a message or wants "to control
>>> expiration of content they create".
>>
>> Furthermore, let's not forget that while maybe in US every possible
>> imaginable thing can be covered by copyright law, in sane countries
>> copyright only applies to "works". Work has to be creative.
> 
> That applies in the US also.
> 
>> If I just send you an email
>> saying "pay me back my $200 you stupid bastard", it doesn't make it a
>> copyrighted work.
> 
> It depends on how you say it.  The above statement isn't original
> so because of that alone it's not creative.

So how can an email be automatically copyrighted when its originality
depends on the contents? 


/Per Jessen, Zürich


Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/2/2011 12:19 AM, Mariusz Kruk wrote:
> On Wednesday 02 of March 2011, Patrick Ben Koetter wrote:
>>>>>  From a legal perspective I will point out that any e-mail you
>>>>>
>>>>> receive is (at least in the US, but most other countries too)
>>>>> considered copyrighted by the sender.  Under copyright law the
>>>>> sender has the right to control expiration of content they create,
>> German law will not work in this case for the same reason it won't for
>> email disclaimers too. The rationale is that "one-sided agreements rescind
>> a contract", which is the case if a sender declares e.g. a copyright on a
>> message or wants "to control expiration of content they create".
>
> Furthermore, let's not forget that while maybe in US every possible imaginable
> thing can be covered by copyright law, in sane countries copyright only
> applies to "works". Work has to be creative.

That applies in the US also.

> If I just send you an email
> saying "pay me back my $200 you stupid bastard", it doesn't make it a
> copyrighted work.

It depends on how you say it.  The above statement isn't original
so because of that alone it's not creative.

> Furthermore, many copyright laws have "permitted use"
> (sorry, don't know the right english term for it) instead of fair use which
> explicitly says what can be done with a work after its first publishing. And
> this use cannot be limited by any contract,

Untrue when it comes to electronic works, as a result of WIPO Copyright 
1996.

Ted

Re: Should Emails Have An Expiration Date

Posted by Mariusz Kruk <Ma...@epsilon.eu.org>.
On Wednesday 02 of March 2011, Patrick Ben Koetter wrote:
> > >> From a legal perspective I will point out that any e-mail you
> > >>
> > >>receive is (at least in the US, but most other countries too)
> > >>considered copyrighted by the sender.  Under copyright law the
> > >>sender has the right to control expiration of content they create,
> German law will not work in this case for the same reason it won't for
> email disclaimers too. The rationale is that "one-sided agreements rescind
> a contract", which is the case if a sender declares e.g. a copyright on a
> message or wants "to control expiration of content they create".

Furthermore, let's not forget that while maybe in US every possible imaginable 
thing can be covered by copyright law, in sane countries copyright only 
applies to "works". Work has to be creative. If I just send you an email 
saying "pay me back my $200 you stupid bastard", it doesn't make it a 
copyrighted work. Furthermore, many copyright laws have "permitted use" 
(sorry, don't know the right english term for it) instead of fair use which 
explicitly says what can be done with a work after its first publishing. And 
this use cannot be limited by any contract, so even if the viewpoint of 
copyright was valid in US (I won't debate on this since I'm not an expert on 
US copyright law) it's definitely invalid with many other law systems.

-- 
\------------------------/ 
|  Kruk@epsilon.eu.org   | 
| http://epsilon.eu.org/ | 
/------------------------\ 

Re: Should Emails Have An Expiration Date

Posted by Patrick Ben Koetter <p...@state-of-mind.de>.
* Ted Mittelstaedt <te...@ipinc.net>:
> On 3/1/2011 11:55 AM, John Levine wrote:
> >> From a legal perspective I will point out that any e-mail you
> >>receive is (at least in the US, but most other countries too)
> >>considered copyrighted by the sender.  Under copyright law the
> >>sender has the right to control expiration of content they create,

German law will not work in this case for the same reason it won't for email
disclaimers too. The rationale is that "one-sided agreements rescind a
contract", which is the case if a sender declares e.g. a copyright on a
message or wants "to control expiration of content they create".

It might have worked back in the days of half-way covenants
<http://en.wikipedia.org/wiki/Half-Way_Covenant> ... ;)

p@rick




> >
> >I really think it would be a good idea for people to refrain from
> >playing Junior Lawyer here.
> >
> >I know just enough about copyright law to know that this claim is
> >nonsense.
> >
> 
> No, it is not nonsense.  Copyright law does allow the content creator
> to specify duration of use.  If you go view a movie in a movie theater
> you buy a ticket for a single viewing, you do not automatically get
> to view it multiple times just because you bought a ticket.
> 
> Ted
> 
> >R's,
> >John
> 

-- 
state of mind
Digitale Kommunikation

http://www.state-of-mind.de

Franziskanerstraße 15      Telefon +49 89 3090 4664
81669 München              Telefax +49 89 3090 4666

Amtsgericht München        Partnerschaftsregister PR 563


Re: Should Emails Have An Expiration Date

Posted by "David F. Skoll" <df...@roaringpenguin.com>.
On Tue, 01 Mar 2011 21:15:13 -0800
Ted Mittelstaedt <te...@ipinc.net> wrote:

> Please, instead of just randomly selecting terms related to copyright,
> why don't you try to make a coherent and logical argument why
> expiration dates on copyrighted material are illegal and should be
> ignored.

The purpose of copyright is to encourage the creation of works.  Copyright
is not a blanket gift to content creators; it's a deal between society
and content creators.

Content creators get time-limited protection for their works in return for
their works eventually passing into the public domain.  Unfortunately, given
the intense lobbying efforts by RIAA, MPAA and friends, people seem to
forget the second half of the bargain.  And the never-ending extensions
to copyright term passed by US lawmakers is helping to subvert the bargain.

Something that expires cannot pass into the public domain and therefore
violates the copyright bargain between society and content producers.

Regards,

David.

Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/1/2011 8:55 PM, John Levine wrote:
>>> I know just enough about copyright law to know that this claim is
>>> nonsense.
>
>> No, it is not nonsense.  Copyright law does allow the content creator
>> to specify duration of use.  If you go view a movie in a movie theater
>> you buy a ticket for a single viewing, you do not automatically get
>> to view it multiple times just because you bought a ticket.
>
> I think this would be a good time to go look up terms like "fixation",
> "first sale", and "fair use" before further embarassing yourself.
>
> Free hint: movie tickets aren't copyright licenses.
>
> R's,
> John

I already mentioned fair use in the original post.  You are welcome to
argue that if I sent out an e-mail with an expiration on it that if
you overrode that expiration you could do so under Fair Use but I
think you are nuts if you think a court would agree with that.

As far as first sale, that absolutely would apply.  If I put an 
expiration date on an e-mail you could certainly sell or forward it
or whatever BEFORE the expiration date was hit.  But whoever had
the copy of my copyrighted e-mail would still be bound by the
terms of the expiration and would have to expire the mail.

As for fixation, I have no idea why you think the moment of creation
as any relevance to the discussion.  An e-mail or post when it is sent
from a computer is fixed.

Please, instead of just randomly selecting terms related to copyright,
why don't you try to make a coherent and logical argument why
expiration dates on copyrighted material are illegal and should be
ignored.

Ted

Re: Should Emails Have An Expiration Date

Posted by John Levine <jo...@taugh.com>.
>> I know just enough about copyright law to know that this claim is
>> nonsense.

>No, it is not nonsense.  Copyright law does allow the content creator
>to specify duration of use.  If you go view a movie in a movie theater
>you buy a ticket for a single viewing, you do not automatically get
>to view it multiple times just because you bought a ticket.

I think this would be a good time to go look up terms like "fixation",
"first sale", and "fair use" before further embarassing yourself.

Free hint: movie tickets aren't copyright licenses.

R's,
John

Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 3/1/2011 11:55 AM, John Levine wrote:
>>  From a legal perspective I will point out that any e-mail you
>> receive is (at least in the US, but most other countries too)
>> considered copyrighted by the sender.  Under copyright law the
>> sender has the right to control expiration of content they create,
>
> I really think it would be a good idea for people to refrain from
> playing Junior Lawyer here.
>
> I know just enough about copyright law to know that this claim is
> nonsense.
>

No, it is not nonsense.  Copyright law does allow the content creator
to specify duration of use.  If you go view a movie in a movie theater
you buy a ticket for a single viewing, you do not automatically get
to view it multiple times just because you bought a ticket.

Ted

> R's,
> John


Re: Should Emails Have An Expiration Date

Posted by John Levine <jo...@taugh.com>.
> From a legal perspective I will point out that any e-mail you
>receive is (at least in the US, but most other countries too)
>considered copyrighted by the sender.  Under copyright law the
>sender has the right to control expiration of content they create,

I really think it would be a good idea for people to refrain from
playing Junior Lawyer here.

I know just enough about copyright law to know that this claim is
nonsense.

R's,
John

Re: Should Emails Have An Expiration Date

Posted by Ted Mittelstaedt <te...@ipinc.net>.
On 2/28/2011 7:20 PM, John Levine wrote:
>> I do like the idea with respect to alerts; if email programs (especially
>> those on smart phones) would know to avoid alerting you of unread +
>> expired messages, that could be quite beneficial.  Especially if I could
>> set expiration times with thunderbird filters.
>
> If people keep at it, they may yet reinvent RSS which, I note, T'bird
> supports reasonably well.
>
> The main appeal of Expires: is to spammers and near-spammers, who hope
> they can make the mail go away before people complain about it.  As I
> pointed out to Ken Magill, usenet has had an Expires: header for
> decades, the design of usenet makes it cheap to implement, and it has
> never been useful in practice.
>

Well for starters folks, most of what has been discussed here is a
pile of baloney.

For starters, there IS ALREADY AN EXPIRATION HEADER for e-mail.  It was
first defined in RFC 1327, it is:

Expiry Date Indication
       Supported as new RFC 822 header (Expiry-Date:).  In general,
       no automatic action can be expected.

This header definition is also expanded on in RFC 2076.

However I will point out that RFC 2076 discusses this entire expiration
thing.  RFC 2076 permits use of many Usenet News article headers in
e-mail messages with the caveat that just because it's permitted does
not mean that MUAs are required to support it.

Because Usenet uses "Expires:" as a header, RFC 2076 basically strongly
suggests that if your going to use an expiration header in an e-mail
message, that you use the Usenet one, not the X.400 one (unless your
communicating with an X.400 system of course) from RFC 1327.

As for spammers wanting an expires header to make spam go away before
you can complain about it, this is a joke, right?

If MUA's supported an Expires header than us administrators could
configure our spamfilters to put a 5 day expiration header in anything
we get that we think is spam.  That would HELP us.  It is the last thing
a spammer wants.

Be serious.  Any MUA that implements an Expires: header would do the 
same thing that MUA's do with X-Confirm-Reading-To: 
Disposition-Notification-To: or Return-Receipt-To: headers - when the 
MUA encounters
the header it queries the user if it wants the user to act on it -
or it silently does it or ignores it, depending on the setting of
a checkbox in the MUA configuration.  Implementing Expires: would be
no problem at all.

 From a legal perspective I will point out that any e-mail you
receive is (at least in the US, but most other countries too)
considered copyrighted by the sender.  Under copyright law the
sender has the right to control expiration of content they create,
the movie houses are doing this with digital copies that are
time-limited and included with blue-ray disc purchases.  Thus if
a corporation suddenly has e-mail disappearing from it's servers
due to expiration dates inserted by the e-mail creator they are
absolutely protected from a legal point of view - because of the
demands of copyright law.

If a court subpoenas from company X an e-mail that the sender
had copyrighted and forced to expire, then company X can merely
state that they don't have the e-mail because they were following
the demands of copyright law that says they must expire the e-mail
when the sender (copyright holder) wanted it to be expired.  Legally
a company or individual cannot be prosecuted for following the law,
so no matter how much the court might have really, really wanted
them to retain a copy of the e-mail, they cannot punish them for
failing to comply with the subpoena.

Where it would get very interesting is that many times e-mails
are cut and pasted together.  In that case the actual copyright
ownership is very murky.  Normally you would argue that the
last person to send the message is the copyright holder.  For
example in this particular post I am including copyrighted material
from John Levine (the first part of the posting) BUT because I am doing 
it under the doctrine of Fair Use, the ENTIRE post, including his parts, 
is under MY copyright.  If he were to sue me for infringement
if a judge sided with my interpretation of it as Fair Use then he
would lose.  Thus, if I put an expiration date on this, even if
he objects to expiration dates, he is screwed.  But if the judge sided
with HIS interpretation, then -I- would be screwed.  In this kind
of case, a corporation basically is in a dammed if they do, dammed
if they don't situation, so basically whether or not to honor Expires: 
is going to end up being a decision that most corporations would
probably take the approach that in most cases they are better off with 
LESS of an e-mail trail so if they have any excuse to be able to
legally "shred" e-mail early, then they would take it.

Ted