Federal agencies must publish all public data in a machine-readable format and appoint chief data officers to oversee open data efforts under a new law.

President Trump on Monday signed the OPEN Government Data Act into law, bringing years of debate and legal hair-splitting to a close. The transparency measure was tucked inside a larger bill to support evidence-based policymaking.

The signing of the bill marks “a historic day for the open data movement,” said Sarah Joy Hays, acting executive director of the Data Coalition, which has worked with lawmakers to shape the bill since 2015.

The law requires agencies to release all non-sensitive data to the public in a format that allows for easy data analysis and largely prohibits them from restricting how that information can be used. It also mandates the Office of Management and Budget help agencies stand up “comprehensive data inventor[ies]” that include metadata on every dataset they publish.

The General Services Administration must create an online portal where the public can search and access information published by each agency.

Under the act, agencies must also designate chief data officer to manage the organization’s data management and coordinate efforts across the government. Many agencies have already appointed people to serve that role, but the law codifies the position and establishes a Chief Data Officer Council to advise the government on open data efforts.

The Trump administration has long evangelized government data’s potential to spur economic growth, advance research and enable agencies to streamline internal processes. The law would not only support those efforts, but it could also offer White House officials guidance as they put the finishing touches on the federal data strategy.

The law will officially go into effect 180 days from now and the Government Accountability Office is charged with reporting on agencies’ implementation efforts every two years. Based on previous open data orders, however, it could take some time for the public to see results.

The DATA Act, which requires the government to publish spending data online, went into effect in 2014, but agencies are still struggling to comply with the measure. Daniel Schuman, policy director for the government transparency advocate Demand Progress, told Nextgov the OPEN Government Data Act could see similarly slow adoption without a concerted effort to get agencies on board.

“The legislation's effectiveness will depend greatly on OMB's implementation, which as our experience with the DATA Act has shown will require vigorous congressional and civil society engagement,” he said.