RE: homemade inkjet printer head

From: Bathsheba Grossman (
Date: Mon Jun 10 2002 - 21:10:16 EEST

On Sat, 8 Jun 2002, Jonathan Handel wrote:
> You haven't violated their rights, because they've impliedly licensed you
> to do what you do for them. And you probably haven't gained any rights in
> their design beyond the rights to use it on this one occasion to produce
> the part - but remember that the client relying on the law in an untested
> area. This always introduces at least some uncertainty.

I suppose so - common sense isn't what it used to be. This kind of
thing is also a problem with art foundries; they often take
unauthorized molds of work they like or think salable.

> In any case, if building the part means that you create an STL file from
> the CAD file, the STL file is a derivative work based on the CAD
> file. Absent a contract, the rights in the STL file are frozen (if the STL
> file is protectible by copyright at all): you have no right to use it
> (after completion of the job), because the client owns the copyright and
> perhaps other rights in the underlying work.

With you so far. I'm making an authorized derivative work, and I
can't go beyond the type and quantity that are authorized.

> But the client also has no
> right to use the STL file, because you own the copyright in the STL
> file. This may not be the result the client intends, but it's good for
> you, since it forces the client to come back to you, rather than another
> shop, if they want more copies of the part.

Hmm. Can't the client just go and authorize someone else to generate
another STL file from their data? I mean, I may own this particular
STL file, but it's hard to imagine that I've acquired a lock on the
act of creating one. If somebody else did create another one it
probably wouldn't be identical to mine.

> If I were representing the client, I'd want an agreement, in order to be
> very sure that the vendor acquires no rights in my design, and also in
> order to acquire rights in the STL file (and I'd want the STL file to be a
> deliverable). From the client perspective, there are other reasons for an
> agreement as well, such as confidentiality. From the vendor perspective,
> there are also good reasons for an agreement, such as limitation of liability.

Most of my customers don't use NDA's, and personally I think they're
all insane. They're used to sending waxes to foundries, where at
least some work and expense is required to steal a design. It
completely hasn't occurred to them that this is data - the same stuff
that gets emailed to all their friends every time their machine picks
up a virus - and I can steal or release it with no effort at all, even
by accident.

> The photcopying scenario is different, because Kinko's doesn't create a
> derivative work as part of the process of copying, assuming they use an
> analog copier. Even if they use a digital copier, which they probably do
> these days, the digital data is probably not stored in the machine once the
> job is complete, so the question is pretty moot. Also, I'd wonder whether
> a scan file is considered a derivative work or just a copy, a question I
> haven't explored.

If you have time, I'm curious: how/when is a copy not a derivative

Bathsheba Grossman                                         (831) 429-8224
Creative prototyping                             

For more information about the rp-ml, see

For more information about the rp-ml, see

This archive was generated by hypermail 2.1.4 : Tue Jan 21 2003 - 20:13:54 EET