Mr. London, the partner in charge of the audit practice for KPMG in Southern California and a prominent figure in Los Angeles business circles, said he passed on confidential data about two of his clients — the nutrition supplement maker Herbalife and the footwear manufacturer Skechers. As a result, KPMG resigned as auditor for the two companies. “What I have done was wrong and against everything that I had believed in,” Mr. London, who lives in Agoura Hills, Calif., said in a statement issued through his lawyer. “I spent nearly 30 years at KPMG and I dedicated my entire life to that firm.” Mr. London, according to his LinkedIn page, has been at KPMG since January 1984, immediately after graduating from California-State University in Northridge, Calif.