The rulings, which mean that government officials will have to provide full details of meetings and engagements when requested, were welcomed by transparency campaigners although they could be still be subject to appeal.
Commenting on the rulings, Francis Ingham, director general of the PRCA, said: "For too long, the lobbying industry has taken the brunt of abuse from the media and the public, who are justifiably angry at those politicians who decide to put financial interest over public service.
"Once again, transparency campaigning exposes the overwhelming flaws in the Lobbying Act: there is a great deal of information already available from the side of the politicians. The answer is openness from their side, rather than the overwhelmingly knee-jerk reactions to posed ‘lobbying scandals’ that involve no lobbyists.
"This gets to the heart of lobbying ‘transparency’: the acceptance and understanding that public scrutiny of politicians’ diaries will do more to get Parliament in order than any onerous industry regulations."