All scientific data from NRAO telescopes are stored in an archive (with the current exception of some pulsar data taken with the GBT's GUPPI backend). The archive contains the raw data: GBT files in FITS binary table format, export files from the VLA, and FITS-IDI files from the VLBA, including correlated data from any non-VLBA telescopes that have been used in conjunction with the VLBA. These data are reserved for the exclusive use of the observing team for a fixed period after the last observing session of a project has been completed. This proprietary period is 12 months following the last observation.
In certain circumstances (e.g. multi-epoch monitoring projects or projects that require several VLA configurations) the default proprietary period may be lengthened by the NRAO Time Allocation Commitee. Additonally, some Rapid Response Science proposals, in particular "Exploratory Time" and "Target of Opportunity", have shorter proprietary periods. All data, taken as part of instrument calibration, engineering or software testing are immediately public with no proprietary period.