NEW YORK—In a strongly worded opinion, a federal judge dismissed a 2007 lawsuit in which the Equal Employment Opportunity Commission accused Bloomberg Inc. of engaging in a pattern or practice of bias against pregnant women.

“‘J’accuse!’ is not enough in court,” U.S. District Court Judge Loretta A. Preska said in the ruling granting summary judgment. “Evidence is required. The evidence presented in this case is insufficient to demonstrate that discrimination was Bloomberg’s standard operating procedure, even if there were several isolated instances of individual discrimination.

“As its standard operating procedure, Bloomberg increased compensation for women returning from maternity leave more than for those who took similarly lengthy leaves and did not reduce the responsibilities of women returning from maternity leave any more than of those who took similarly lengthy leaves,” Judge Preska ruled.

Quality of evidence not good enough

The judge also criticized the EEOC and the evidence it presented in the case against the company founded by current third-term New York City Mayor Michael R. Bloomberg.

“Even viewing the record in favor of the EEOC, the quality of EEOC’s assemblage of evidence is not the sort courts have found to be sufficient evidence of a pattern of discrimination,” the New York federal judge wrote.

“In a company like Bloomberg, which explicitly makes all-out dedication its expectation, making a decision that preferences family over work comes with consequences. But those consequences occur for anyone who takes significant time away from Bloomberg, not just for pregnant women and mothers.”

The remaining individual claims of discrimination still can proceed, according to the opinion.

Reacting to the ruling, the EEOC said in a statement, “We regret today's decision, and look forward to proceeding with the individual claims and will assess our options.”

A Bloomberg spokesman could not be reached for comment.

While the suit against Bloomberg was dismissed, more such cases have been filed in recent years. A study by the San Francisco-based Center for WorkLife Law found that the number of family responsibility discrimination suits increased from four in 1979 to 329 in 2008. Eighty-eight percent of the plaintiffs were female, and their claims most often concerned pregnancy and maternity leave.