How many partners are in BigLaw? It depends on who’s asking.

More than half of the major law firms in New York City reported different partnership numbers to six different entities collecting the information in 2007, according to a study by Stanford law professor Michele Dauber.

Two judges and a consultant point to the discrepancies in a National Law Journal article calling for a uniform definition of equity partner. The authors are U.S. District Judge Nancy Gertner; Massachusetts appeals court judge Fernande Duffly; and Lauren Stiller Rikleen, executive director of the Bowditch Institute for Women’s Success.

The inconsistencies make it “extraordinarily difficult to determine how women and lawyers of color are, in fact, succeeding,” they write. Law firms may report fewer equity partners when seeking to boost partner profit numbers and more equity partners when reporting data on women and minorities.

The article applauds the initial attempt by the career professionals group NALP to require law firms to distinguish between equity and nonequity partners in its annual survey. NALP dropped the effort to collect data on nonequity partners, however, after most of its law firm members refused to supply the information.

“How many equity partners does a firm truly have?” the NLJ article asks. “What is the ratio of men to women, in both equity and nonequity ranks? How many partners are lawyers of color? Without this information, law students and lateral recruits cannot make educated judgments about their future prospects.”