And who was prosecuted?
here is one:
Ex-Senate Intelligence staffer indicted on charges of lying in leak probe
and some confirmation from the fake news media as well -
Analysis | Trump rages about leakers. Obama quietly prosecuted them.
Experts on executive-branch leaks say it's too early to gauge Trump's legacy. But much has been made about the Obama administration's hunt for leakers. Of the 13 people who have been prosecuted under the Espionage Act for leaking secrets, eight were arrested under Obama's administration, according to Alexandra Ellerbeck, senior Americas and U.S. researcher with the Committee to Protect Journalists.
And prosecutors under Obama have spied on journalists and named a journalist an “unindicted co-conspirator,” according to the New York Times. Ellerbeck said that's just a step away from arresting a reporter for writing a story — and raises dangerous constitutional issues about freedom of the press.
The OP was about Obama, not the Senate