Trypsin inhibitors (TI) are naturally present in grains of oilseed, legume and cereal crops. These proteinaceous compounds have nutritional and health implications to humans and animals. The American Oil Chemists Society (AOCS) approved an official Method Ba 12-75 in 1975 for measuring TI in soy products, based on Kakade et al. 1974 (Cereal Chem. 51:376-382). The method was reapproved in 2017. For the past three quarters, AOCS has undertaken a collaborative study on a proposed AOCS method, Ba 12a-20, which is a significantly modification of the current method, based on two recent publications (Liu, 2019, J. Am. Oil Chem. Soc., 96: 619–633; 635–645). The new method features the enzyme-last sequence, a single sample extract in duplicate, and 5 mL total assay (half of the current method), with an expanded sample scope to include soybeans, pulses, beans, grains and related products. For the study, 15 collaborative labs from North America, South America, Europe, and Asia were recruited to analyze TI activities in 11 coded samples provided. This presentation reports the results of this collaborative study, while a manuscript is being written for publication in J. Am. Oil Chem. Soc. As increasing volumes of plant proteins are being used for food or feed in recent years, it is increasingly important to have a standard method that can measure TI in various protein products with high sensitivity and precision.