DataCite DOIs describe resources such as datasets, samples, software and publications with rich metadata. An important part of this metadata is the description of connections between resources that use persistent identifiers (PIDs) provided by DataCite and others (Crossref, ORCID, ROR, ISNI, IGSN, etc.). Together these resources and their connections form a graph, the PID Graph (Fenner &

DOI metadata provenance is describing the history of a particular DOI metadata record, i.e. what changes were made when and by whom. This information is now stored and provided via an API for all DOI registrations since March 10, 2019.

Persistent identifiers (PIDs) are not only important to uniquely identify a publication, dataset, or person, but the metadata for these persistent identifiers can provide unambiguous linking between persistent identifiers of the same type, e.g. journal articles citing other journal articles, or of different types, e.g. linking a researcher and the datasets they produced.

Today we are announcing our first new functionality of 2019, a much improved search for DataCite DOIs and metadata. While the DataCite Search user interface has not changed, changes under the hood bring many important improvements and are our biggest changes to search since 2012.Faster Indexing Newly registered (and tagged findable) DOIs now appear in the DataCite Search index within a few minutes, compared with the previous up to 12 hour lag.

All DataCite DOIs have associated metadata, described in the DataCite Metadata Schema Documentation (DataCite Metadata Working Group (2017)), validated and stored as XML in the DataCite Metadata Store (MDS). These metadata are then made available via DataCite APIs and services. For these services XML is not always the best format, and we are thus providing the metadata in other formats, most notably JSON.

There is a need for the consistent and credible reporting of research data usage. Such usage metrics are required as an important component in understanding how publicly available research data are being reused.

We know that software is important in research, and some of us in the scholarly communications community, for example, in FORCE11, have been pushing the concept of software citation as a method to allow software developers and maintainers to get academic credit for their work: software releases are published and assigned DOIs, and software users then cite these releases when they publish research that uses the software.

Today DataCite is launching DOI Fabrica, the next generation of DataCite’s DOI registration service, replacing the Metadata Store (MDS). This is the biggest and most important product release DataCite has done in many years, and the result of nine months of hard work by the entire DataCite team. DOI registration is the core service that DataCite is providing to its members and the data centers they work with.

While it is a best practice for DOIs (expressed as URL) to send the user to the landing page for that resource (Starr et al., 2015), sometimes we want something else: metadata , e.g. to generate a citation, or to go to the content itself. The easiest way to do that is to use DOI content negotiation.

Three weeks ago we started assigning DOIs to every post on this blog (Fenner, 2016c). The process we implemented uses a new command line utility and integrates well with our the publishing workflow, with (almost) no extra effort compared to how we published blog posts before. Given that DataCite is a DOI registration agency, we obviously are careful about following best practices for assigning DOIs.

On Tuesday the journal PLOS ONE celebrated its 10th anniversary (see blog post by PLOS ONE Editor-in-Chief Jörg Heber and blog post by PLOS ONE Managing Editor Iratxe Puebla and PLOS Advocacy Director Catriona MacCallum). PLOS ONE (and PLOS) have changed scholarly publishing in many ways, from a DataCite perspective probably most importantly via the data policy updated in February 2014 that states that PLOS ONE was not the first journal with a