Preserving Data in Government Act of 20 20 This bill requires federal agencies to preserve public access to existing open datasets and prevent the removal of existing datasets without public notice. Specifically, the bill requires that any open government data asset that is made available to the public for at least 90 consecutive days (1) remain machine-readable, available in an open format, and part of the worldwide public domain or, if necessary, be published with an open license; and (2) not be altered in such a way as to decrease its machine-readable nature. It shall not be a violation of such requirement to alter (1) the digital location or format of any open government data asset for routine asset maintenance or long-term archiving if such alteration does not decrease the open public accessibility or the machine-readable nature of the data, or (2) the contents of such data asset to update it or correct an error. Any substantial alteration of the data asset's contents shall be recorded in a log that is made available to the public. An agency may remove such data asset from public availability under specified circumstances, such as if the agency determines that the data asset is too costly to maintain or does not provide sufficient value to the public. This bill shall not apply to such data asset that is required to be removed from public availability or altered under another provision of law.