An inscription pen was a writing instrument.
In 2371, Quark was selling inscription pens on Deep Space 9 during the Bajoran Gratitude Festival that could be used to write on renewal scrolls. The pens were engraved with "Deep Space Nine's Third Annual Gratitude Festival", the date of the event and included a portrait of Deep Space 9 by Ermat Zimm. Quark claimed the pens had been blessed by Vedek Redab before his death. Lwaxana Troi later bought an inscription pen and gave it to Odo as a present. (DS9: "Fascination")