From the PubChem Blog:
Sometimes information provided to PubChem by data contributors becomes outdated. To address this, PubChem is introducing a “legacy” designation for collections that are not regularly updated. This “legacy” designation applies to project/contributors that appear to no longer be active, as well as to their individual records. This designation will help PubChem users quickly identify records that may have out-of-date information and/or hyperlinks.
A “legacy” designation is arrived at via a semi-manual, semi-automated procedure. It involves aspects of examining contributor account information, individual records, and user reports. For example, if the depositor website does not work for a period of time, attempts are made to contact the submitting organization. If PubChem staff are unable to make contact with the data contributor or if an organization is no longer updating records, a legacy designation may be initiated. Please note that a “legacy” designation can be removed at any time, when contact is reestablished and updates resume.
If a data contributor is designated as “legacy”, all records deposited by the contributor are also designated as “legacy”. While still searchable, these records will clearly indicate that they are “legacy”. Please note that “legacy” records will not be shown in the “Chemical Vendors” section of Compound Summary pages. In addition, in the “Substances by Category” section of the Compound Summary page, “legacy” substance records only will be found under “Legacy Depositors”.
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