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Proprietary Rights

Proprietary Rights on HST Data

In accordance with NASA policy, all science data from the Hubble Space Telescope is archived with a one-year proprietary period by default. This period may be extended or shortened at the request of the principle investigator (PI) and on approval by the STScI Director's Office. Calibration data (i.e., data obtained under calibration proposals), by default, carries no proprietary period; neither does engineering data, calibration files (derived from calibration observations), and observatory monitoring data.

In addition to the regular proprietary period, observations by General Observers (GOs) which are found to be duplicates of concurrent observations by a Guaranteed Time Observer (GTO) may be placed under restriction. Data under restriction (or "embargoed") cannot be distributed to the GO until the restriction expires (usually, when the GTO data goes public).

Policy for Submitting a Proprietary Rights Modification

Requests for proprietary rights modifications (extensions, reductions, and/or restrictions) are handled by the archive help desk or send mail to You must sign in with your MyST account to use the web portal. The help desk staff will forward all requests to the appropriate authorizing officials. All requests must go through an approval process before being enacted.