YESTERDAY's swoop on some 100 offices linked to the Allied Group came about as a result of information unearthed by Nicholas Allen in the course of his probe into transactions within the group and its partners. The 500-page report tabling his findings has been with the Financial Secretary, Hamish Macleod, since August 28, and has already cost $41 million in public funds. Mr Allen, of Coopers and Lybrand, was appointed on August 12 to conduct the investigation into Allied Group and nine linked companies. He was appointed by the Financial Secretary under Section 143 of the Companies Ordinance (Chapter 22) to investigate the affairs of Allied Group, Allied Properties, Crusader Holdings, Paragon Holdings and Wai Yick. The Financial Secretary directed Mr Allen to investigate and report on, in particular, big transactions - including acquisitions and disposals of assets, loans and guarantees, and grant of options) entered into by the companies or their subsidiarie s since January 1, 1990. Mr Allen was also requested to investigate and report on dealings over the same period by the companies and each others' subsidiaries and in shares of Allied Industries International, Asia Securities International, Paramount Printing, Santai Manufacturing and Tung Wing Steel Holdings. Apart from Allied Industries, all have been sold off. But the inspection soon escalated as more and more information was unearthed, and Mr Allen was forced to seek further funds from the Government, sparking off a furore in the Legislative Council. Legislators, led by Emily Lau Wai-hing, attacked the Government for dipping into public coffers but failing to inform the public of the findings. Partly as a result of this pressure, the Government has pledged to make public as much of the report as it legally can. Shareholders too have seen their money channelled into the investigation, as Allied has launched a series of bids in court in connection with the case. The judge's ruling on the latest appeal to apply for leave to apply for judicial review will be handed down today. Before yesterday's raid, Allied had planned to return to the courts tomorrow to seek leave to apply to the Privy Council in London. Allied's case revolves around allegations of prejudice in the inspection, with company directors claiming there was a witch hunt against Lee Ming Tee by regulatory authorities. Until the end of last year - four months after the investigation was launched - shareholders of Allied Group had shouldered a $28.52 million burden in connection with the probe. Group spokesman John Wong has said a provision of $7 million to cover this year's legal fees were set aside in the books for 1992. Allegations that one of the regulators was ''out to get'' Mr Lee followed an earlier case brought by director Ronald Tse Chu-fai to prohibit the inspector from carrying out an investigation of the company as it relates to him.