For the 24 schools I applied to....
1. SUNY Upstate (State University of New York at Syracuse) straight out say that they will only acknowledge 2 letters of rec (I believe one science and one non-science)
2. Wake Forest seems to only want 2 letters only (Again one science and one non-science). They even want each letter writer to fill out a recommendation form, unless a comittee letter is sent.
The others will tell you the min. letters they want, but don't specify the max. or set the max at around 5 letters:
Albert Einstein, Dartmouth, Emory, Georgetown, Harvard, Jefferson, Johns Hopkins, USC, Loma Linda, Med College of Wisconsin, Mount Sinai, Northwestern, Stanford, Tufts, U of Chicago Pritzker, U of Pennsylvania, U of Virginia, Vanderbilt, Yale, Columbia, and NYU
Finally I don't know about the policy from the 24th school, UCLA, which hasn't sent me any secondary yet.