The Agency for Health Research & Quality (AHRQ) has released their public access plan – a response to the OSTP memo of nearly two years ago. Details of the plan are available here: http://www.ahrq.gov/funding/policies/publicaccess/index.html
Very briefly: AHRQ states that authors will be required to submit scholarly papers to PubMed Central. AHRQ-funded researchers will also be required to submit a data management plan with grant proposals. Sharing of data no later than “the acceptance [date] for publication of the main findings from the final dataset” will be required unless researchers can explain why this is not possible. The policy will be effective by Oct. 2015.