The core challenge in the US Public Access program is to precisely identify the funders of the research that leads to a given journal article. This sounds easy but it can be a difficult and complex process. The US Government is a vast and complex organization, with hundreds of different offices sponsoring research. Moreover, each office can be referred to in many different ways, creating a major name disambiguation problem in the funder data.
All authors have institutions -- either a university or a research institution. Those institutions have a huge stake in ensuring that their researchers comply with their funder requirements (and they already review all grant applications). Institutions are hence the ones in the position to monitor their own researchers' journal article output, ensure that the funder (if any) is specified in the repository metadata for each published article, and, most important of all, ensure that the deposit is done within the required time-frame (see BOAI recommendation above).Repository deposits are time-stamped. Researchers can even be asked to deposit the journal's acceptance letter (in closed access) alongside the final refereed draft, for record-keeping and compliance monitoring purposes. The institution can thereby systematically monitor and ensure timely compliance with funder (and institutional) deposit mandates. (The repository software and the Copy Request Button can then handle any allowable publisher embargo periods in a simple, straightforward way --via the Button till the embargo elapses, and then the deposit automatically becomes OA.)
CHORUS and FundRef are attacking this funder identification problem using a standardized menu of funder names and DOIs. The basic idea is that the submitting author will pick out the standard names of all the offices that contributed to the research that underlies the submitted article. Again this sounds simple but it is not, because building a comprehensive taxonomy of all possible funders is far from simple.
To begin with they have elected to build this menu to identify all the funders in the world, not just the US Federal funders. As a result the menu of funders already has six thousands names and it will probably have many thousands more before it stabilizes. The size of the funder list alone thus creates a big discovery problem, because many funders have similar names.
Then there is the hierarchy problem, especially within the vast US Government complex. Funding offices occur at many different scales, which are arranged within one another in the tree-like organization chart. For example in the US Energy Department there may be five or more layers of funding offices. Saying which layer should be named in the funding data for a given article is not simple. Moreover if offices in different layers are named for different articles, then the resulting data will have to somehow be aggregated by layer in order to be useful. To make matters worse there are also cross cutting programs that involve multiple offices. In short any taxonomy of US Federal funding offices is going to be a complex system, not a simple listing.
Given these complexities it may be better to have an editor name the funders based on the acknowledgements section of the article, rather than presenting the author with a complex taxonomy of possible funders. There seems to be some experimentation in this direction, but it is a labor intensive solution. The question is also whether the resulting data would be accurate enough for agency purposes; given that acknowledgement has been a relatively informal process. There is also the question of when to collect this funder data, given the labor involved. Should it be upon submission or after acceptance?"