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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) should be sent to the archive hotseat ( The hotseat staff will forward all requests to the appropriate authorizing officials. All requests must be approved by the Director's Office before being enacted. The hotseat is chosen as the contact point to simplify the request process and to assure that all requests receive prompt attention.

Requests for proprietary rights modifications should be received at least 2 weeks before the current expiration date of the proprietary period. Requests received after this cannot be assured of timely consideration and may result in data becoming public. Requests to extend the proprietary rights on data that has already become public cannot be considered.

Specific information is required by STScI in order to evaluate a proprietary rights modification request. The required information depends on the nature of the request. The information can be provided either by using our WWW proprietary rights request submission utilities or by retrieving and completing the appropriate postscript form. Use of the WWW submission utilities is strongly recommended.

If you opt to use the postscript forms, and you wish to request an extension or reduction of the proprietary period, please obtain and provide the information given in the file proprights/ If the request is for a restriction on GO access, the relevant file is proprights/

Proprietary Rights Modification Forms