There is a proprietary period of 1 year during which, subject to the caveat below, the data from an observation will only be distributed to the Principal Investigator of that proposal. After this one year period, the data become available to the community. The 1 year period shall start from the time when the data are delivered to the Principal Investigator of that proposal in a usable form, i.e. appropriate data processing having been applied and with suitable calibrations from the ISO Science Operations Centre. For programmes which have their observations distributed throughout the lifetime of ISO, the 1-year period shall start from the delivery to the observer of the last observation in the programme.
In accordance with ESA's rules concerning information and data, ESA retains the right to use any data from the ISO guaranteed or open time programmes for instrument evaluation, diagnostic and calibration purposes, while maintaining scientific confidentiality during the proprietary period. ESA also reserves the right to use any data for public relations purposes; in this case, due acknowledgment shall be given to the Principal Investigator of the proposal and to the Principal Investigator of the consortium that built the instrument.
Any publication based on data from ISO observations shall be acknowledged by a footnote on the initial page of the paper: ``Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA''.