Business Week said it fired its broadcast editor Friday for violating the magazine's code of ethics and possibly trading on advance knowlege of stocks mentioned in issues before they were released to the public.

S.G. "Rudy" Ruderman, who had broadcast market and business news for Business Week since 1981, failed to disclose to the magazine "all the (stock) trades he made and the full extent of his holdings" in accordance with the ethics code, magazine spokeswoman Mary McGeachy said.McGraw-Hill Inc., Business Week's publisher, learned late Thursday from the New York Stock Exchange's surveillance unit that Ruderman "may have made four or five trades in 1988 involving stocks mentioned in the magazine's `Inside Wall Street' column," McGeachy said.

The firing came a day after the first criminal charge was filed in the spreading scandal. A stock broker who had been fired by Merrill Lynch & Co. for suspicious trades was charged with mail fraud Thursday, and his lawyer said he would plead guilty.