Calcutta, May 27 :    Calcutta, May 27:  The Securities and Exchange Board of India (Sebi) has dealt a body blow to Calcutta-based broker Ajay Kayan by barring his firm, C. Mackertich Ltd, from trading in securities for six months for various offences, including concealment of off-market transactions and unauthorised carry-forward deals-or badla in the market parlance. The market regulator's order, passed today, said the leading corporate member of the Calcutta Stock Exchange was being suspended for 'acting as a sub-broker without obtaining registration from it, not maintaining a clear segregation between clients' funds and its own money, not reporting off-the-floor transactions to stock exchange and indulging in unauthorised carry-forward transactions'. Reacting to the market regulator's order, Kayan said: 'I have not been dealing on the Calcutta Stock Exchange for quite some time, and this order makes hardly any difference to me. It is irrelevant to me whether or not I can trade on the Calcutta Stock Exchange.' He said the charges brought against C. Mackertich are six years old. Kayan has often been facing the market regulator's wrath. The special court trying cases related to the multi-crore securities scam of 1992, recently attached his properties, his father and C. Mackertich Ltd for alleged involvement. This implies that the court may liquidate assets in possession of these entities for recovery of ill-gotten money, if the charges against them are established. Kayan, who appears to be in no mood to challenge Sebi's order, had moved the Calcutta high court disputing the validity of the special court's order. He had even obtained an injunction on the operation of the special court's order, but the court later withdrew it. He and his firms were probed last year by the market regulator for suspected involvement in the bear hammering that led to a sharp fall in stock prices in March last year. However, Sebi did not take any penal action against his firms, and Kayan claimed that the regulator had given him a clean chit.