Brian Callanan, who works at the Treasury Department as the deputy general counsel, has been given an authorization because he worked recently at a law firm that handled federal housing finance matters after serving as a Senate aide. Mr. Callanan will still be able to handle legal matters related to housing finance, but he has agreed not to communicate with his old law firm. He has been assigned, while at Treasury, to look for federal financial regulations that could be revised or repealed.

Last week, a similar set of 14 waivers covering White House employees was made public, showing that former energy and financial services lobbyists had been granted permission to handle policy matters overlapping with their recent private-sector work.

“Filling the administration with lobbyists and industry officials isn’t going to drain anything but taxpayers’ patience,” said Scott H. Amey, general counsel at the Project on Government Oversight, which requested copies of any waivers or recusals from 54 federal agencies, echoing the requests submitted by the Office of Government Ethics.

Some of the waivers were granted to overcome seemingly minor conflicts: John F. Kelly, the homeland security secretary, was granted a waiver to continue to handle policy matters related to Australia, whose government once paid him for a speech. Heather Nauert, a former Fox News anchor who now serves as State Department spokeswoman, was granted a waiver because she must communicate with Fox as part of her job. In the waiver, she is identified as Heather Norby, her husband’s last name.

The material posted Wednesday also includes a handful of waivers given at the end the Obama administration, including one granted to Susan E. Rice, whose family was an investor in Canadian energy companies, banks and other assets, even while she was President Barack Obama’s national security adviser. This waiver had been issued earlier in the Obama administration, but was revised last year based on changes in the investment portfolio. It was not released publicly before because under law these types of documents — related to the criminal conflict of interest rules — are made public only in response to a formal document request.

Mr. Trump’s ethics executive order adopted language first written by the Obama administration. The order prohibits new federal government officials who have worked as a lobbyist or an industry lawyer in the previous two years from handling matters they were involved with on behalf of their former clients. Waivers allow them to ignore this rule.