The government's lobbying bill is being greeted with scorn by trade unions, campaigners and lobbyists alike.
Ministers face howls of anger after publishing the transparency of lobbying, non-party campaigning and trade union administration bill.
The legislation creates a statutory register covering those whose interests are being represented by third party lobbyists, and the consultants themselves.
But Unlock Democracy said over 80% of the £2 billion lobbying industry - including public affairs professionals who advance the interests of the organisations they work for - would not be covered.
"As we have always said, the problem with lobbying is not the respectable lobbying consultants who abide by a code of practice and already work in a relatively transparent way," director Alexandra Runswick said.
"The problem is the more underhand activity, whether it is employed by consultants, think tanks, law firms, in-house lobbyists or private individuals.
"By establishing such a gaping loophole, the government will simply drive business away from lobbying consultants and into the arms of less reputable agencies."
Francis Ingham, director-general of the Public Relations Consultants Association, tweeted that the bill would deliver "less transparency" rather than more.
But Andrew Lansley, who has unexpectedly been handed responsibility for steering the bill through the Commons, declared the coalition's belief that "sunlight is the best disinfectant" and pledge to extend transparency measures further.
"This bill is about extending that transparency further to give the public more confidence in the way third parties interact with the political system," he commented.
Many of the 'third parties' being clamped down on in the bill are trade unions, who will each be restricted to spending no more than £390,000 on political campaigning.
“British democracy needs lively debate, campaigning and lobbying to maintain an open and fair society in which citizens have a voice and the government listens," constitutional reform minister Chloe Smith said.
"But the involvement of campaign groups and other organisations, whether through lobbying government or public campaigning, must be done in a transparent and open way."
Further limits will be imposed on organisation which campaign for or against a specific party or target their spending at a particular constituency.
The TUC has accused the coalition of legislating out of "pure political spite" rather than genuinely taking action to tackle rich corporate lobbyists.
"Most people will see this bill for what it is – a cynical attempt to deflect growing public concern about the behaviour of rich corporate lobbyists representing hedge funds and private health companies, many of whom donate substantial sums to the Conservative party," general secretary Frances O'Grady said.
"Meanwhile unions campaigning to get the voices of Britain's nurses, factory workers, shop assistants and other employees heard around Westminster are being targeted."
The bill was published after the final prime minister's questions before the summer recess. The exchanges were dominated by Ed Miliband's suggestions that the Conservatives' general election adviser Lynton Crosby, a tobacco lobbyist, had influenced the government's decision to drop its plans to introduce plain packaging for cigarettes.