Hedge fund Luxor Capital Group has stepped up its opposition to a proposed $6 billion deal by Ritchie Bros Auctioneers Inc to acquire a rival firm, saying company executives have strengthened their case for the takeover by manipulating forecasts, according to a report by Bloomberg.

The report cites a presentation made by Luxor as claiming that Ritchie helped justify the move to acquire IAA Inc, by understating the future profitability of its core auction business. The New York-based fund manager goes on to claim that Ritchie’s senior executives lowered the company’s projected growth rate, and increased capital expenditures, in to make the figures add up.

The document is part of the investment firm’s proxy fight against the transaction, which goes to a shareholder vote on 14 March.