Trade Barriers

From: Martin Geiger (Fraunhofer Gesellschaft)
To: RP-ML
Date: Friday, April 8, 1994
Subject: Trade Barriers
     The patent situation is indeed very interesting for all vendors. In my opinion the question whether there are patent violations could only be answered by judgement caused by a charge. I do not claim to have the 
information to assess the exact situation, but here some comments.
     In the beginning of stereolithography (anbout 1980) there were three locations (Minneapolis and California in the USA and in Japan) where activities to the selectively layer by layer curing of photopolymer and building of 3-dimensional parts. The first (US+EP) patent I know about was applied for in August 1984. But, there are some very early published articles to the basic principle, how such a machine could work. Furthermore, in France, there have been very early works, too. Nethertheless, until now there are over 180 patent numbers to stereolithography.
     Regarding all this facts, it could be difficult to achieve a judgement that prohibits a company to sell 
machines based on this principle in general (in Europe). More important are patents to some special details of a machine. So, if there are some patent violations, I think a result will only be achievable in such details. In the event of such a prohibition the concerned company has to find an other way or has problems. But I think it is not our task to examine patents (over 180 in stereolithography and over 35 in SLS) and machines, whether there are patent violations. But it is usefull for resaerch institutes, to have a good overview about patents, because the question of patent could play a dominant role by the search of industrial partners to commercialize own developments.
Regards
Martin