An interlaboratory study (round robin) has been conducted by the RPVOT Working Group of D02.09.0C to determine the precision of the D2272 method on a wide range of test oils responding to oxidation in from 100 to 3500 minutes. This round robin included oils containing various older and modern chemistries. All four base stock groups, I through IV, were included in this study. In addition to the older liquid RR: D02-1666 bath approach, the Quantum Oxidation Test was also used to test equivalence in the method. Data from sixteen laboratories was collected testing eight different oils. Eight of the labs ran the liquid RPVOT and eight ran the Quantum Oxidation Test. The version of the method used was Revision 7 for D2272 RR 2008. This incorporated both the liquid and Quantum Oxidation Test protocols. Precision was determined for each individual protocol and for the both forms of instrumentation combined.