In re Lister, the Federal Circuit repeatedly cited In re Klopfenstein, 380 F.3d 1345 (Fed. Cir. 2004) (link below), a decision that held that a poster presentation that was available for viewing at a meeting for 2-3 days was a “printed publication” under 102(b). This decision has lots of interesting dicta that indicates, for example, that a slideshow with an oral presentation would not necessarily be considered a “printed publication” if no printed copies were available since the slides were only transiently visible. A thesis defense per se would also not be considered a printed publication. Even the brief display of a poster may not qualify as a printed publication, and presentation of the poster at a meeting with a non-copying notice may have disqualified the poster as a printed publication.
So if “your professor” tells you that he or she disclosed the invention in a slideshow or a poster at a scientific meeting, don’t assume that all rights are gone, or even that absolute novelty has been lost abroad. I spoke to a UK associate some years ago who told me that the burden of proof imposed by the court on a defendant who tries to rely on an oral presentation or slideshow as novelty-destroying is extremely high. (I won’t go into detail here, since associates may well differ on this point, and you should contact your own, of course.) ‘Nuff said!