Some 2008-12 Accord, 2008-17 Odyssey, 2009-15 Pilot and 2010-12 Crosstour models (all with V6 engines) may produce an oil leak from the left/front portion of the engine. One likely source of the leakage, reports Honda, is a damaged or deformed gasket at the rocker arm oil control valve.
Referring to the illustration, notice that the oil control valve has both an upper and lower portion. You're only interested in replacing the upper portion of the valve with an updated unit, part # 15810-R70-A04, because it has an improved gasket groove. You'll also want to replace the upper retaining bolts, metal plate and gasket, as shown. The lower portion of the oil control valve should be left undisturbed. If you attempt to loosen its bolts or remove the valve itself you'll cause misfire trouble codes to set in the PCM.