Good question. The administration admitted to the existence of these waivers in May, but refused to disclose their contents to the OGE, which is unprecedented among recent administrations. This secrecy was roundly condemned throughout the federal government, and notably and publicly by George W Bush's former chief ethics lawyer [0].
Trump was eventually forced to back down and the waivers were released, revealing such swampy critters as Michael Catanzaro and Shahira Knight [1].
EDIT: So, "secret" in a more colloquial sense than the technical "classified" definition.
Yeah, I read an article that another user posted. I think I prefer the term 'undisclosed.' At least in my head, secret means someone is in trouble for leaking it. There was a paper trail, for example.
I guess the use is valid, but I'm not sure it's objective. I don't prefer Trump, but I do try to remain objective. Try being the operative word.
The norms of what administrations do changes over time in part because what administrations need to do change over time. It's obviously not helpful to contrast George Washington's executive behavior with George Bush's.
In particular, it's useful to draw a line pre- and post-USSR, as that was a sea change in executive policy. That means Bush 1 / Clinton onward. Other common markers are pre/post Great Society, pre/post WW2, pre/post New Deal, etc.
Trump was eventually forced to back down and the waivers were released, revealing such swampy critters as Michael Catanzaro and Shahira Knight [1].
EDIT: So, "secret" in a more colloquial sense than the technical "classified" definition.
0 - http://www.businessinsider.com/trump-lobbyist-ban-cabinet-wa...
1 - https://www.nytimes.com/2017/05/31/us/politics/lobbyist-ethi...