Above the Law has a list of The ATL 2016 Top Transactional Law Firms by Pedigree, which is a fancy way of saying that the top law firms are ranked more or less by the composite rank of the law school of attendance of a given law firm's "relevant" lawyers (see that link for more information about how law firms were vetted for eligibility in the rankings).
To make sure there is no misunderstanding, we note that Above the Law presents the calculation of the two ranking criteria used as follows:
" “Median School Rank”: Median US News ranking of law schools attended by firm's relevant lawyers.We were gratified to see as an alumnus associate of Paul, Weiss, Rifkind, Wharton & Garrison that the firm ranked in the top 10 (7th and 8th respectively) and that there was a definite cut-off point at position nine.
“Mean School IQR”: Mean of middle 50% of US News rankings of law schools attended by firm's relevant lawyers."
Is that kind of a ranking relevant?
We might say that we did something similar some years ago just for fun in privately assessing some of the nation's highest courts by the rank of the law schools of the judges, and, yes, there was a great deal of difference, for example, between the median rank of the law schools of the Justices of the U.S. Supreme Court as compared e.g. to the Federal Circuit, which wound up in relative mediocrity, which was what we were checking to confirm at the time.