Well you asked Ivo, but as I am a bit puzzled about your question, I'm going to comment anyhow. Do you mean the words engraved on the glass below the signature? Those are Nuutaj√§rvi and below that Notsj√∂ (which is the Swedish name of Nuutaj√§rvi).
Just to add to my previous note: The finnish language source about Finnish (designer) glass collecting mentioned that Kaj Franck was reluctant to have his name engraved on his designs (the article referred to designs from the end of 60s), so sometimes they only bear the name of Nuutaj√§rvi. That has lead to designs by these three master glass blowers (lasinpuhaltaja) - Unto Suominen, Onni Nurminen and Jaakko Niemi - being offered as Kaj Franck's designs.