The continuing saga of the Securities and Exchange Commission versus the Blinder, Robinson & Co. brokerage firm has a new, ironic twist:

For years, the SEC has pursued Blinder, Robinson, a Denver-based "penny stock" firm, contending that it has taken unfair advantage of small investors. Now the SEC finds itself defending itself against allegations that it unfairly discriminates against smaller securities firms -- like Blinder, Robinson.

A D.C. appeals court opinion released last Friday in one of several continuing SEC disputes with Blinder suggested that the brokerage house's defense that it and other small firms had been singled out for unusually harsh treatment could have merit.

"We would be less than candid if we did not flag for the commission our concern that petitioners {Blinder} have mounted a nonfrivolous claim that they have been singled out for disproportionately harsh treatment," the opinion said. "Petitioners list a series of instances which, they contend, demonstrate that the SEC's hand comes down more heavily on smaller, new firms than it does on old-line or at least more established, houses with the 'right sort' of exchange memberships.

" ... It does not exceed our appropriate function to indicate that we have seen warning signs," the opinion said.

"We think as far as the long-term effect of that opinion is concerned, it is that very language ... on discrimination that will be the most significant," said Blinder vice president John Cox. "That is not just Blinder Robinson and one administrative proceeding. It seems to reach out and touch everybody.

"You have to ask yourself how {the SEC} can allow a firm {E.F. Hutton} that pleads guilty to 2,000 felonies to continue in business and find there is no public danger, and {move to} suspend people {Blinder} who have not been accused of a misdemeanor," Cox said.

SEC officials defended the agency's conduct, arguing that the commission proceeds on a case by case basis and does not discriminate against firms outside the Wall Street establishment.

Asked about the allegations of bias, Rodney K. Vincent, general counsel of the SEC's Denver regional office said, "That's just not correct. A review of our arguments would not demonstrate that."

SEC general counsel Dan Goelzer explained why someone reviewing commission enforcement actions might get the mistaken impression that the agency discriminates against smaller, newer firms.

"In a case where the {individual} wrongdoers are still with the firm, I think it is natural the commission is going to be more concerned than in the case where the wrongdoers have been expelled or fired," Goelzer said. "You may frequently find that a large firm is going to terminate somebody who has been involved in an SEC proceeding or securities law violation.

"A small firm, particularly a sole practitioner, isn't going to," Goelzer said. "That might lead to what would appear to be a disparity in treatment. It springs really from the question of whether the wrongdoer is still involved in the firm."

Goelzer disputed the appeals court's comments about possible SEC bias. "I don't accept that conclusion. If there is a feeling on the part of anyone that evidence supports that conclusion, I think they need to look more deeply into the particular cases. ... "

The appeals court opinion concerned SEC charges of securities fraud against the Blinder firm and its president, Meyer Blinder, in connection with an initial public offering of securities of American Leisure Corp. between December 1979 and March 1980.