PurposeThe purpose of this paper is to calculate regional contents in the exports of the major regional blocs to the world, Trans-Pacific Strategic Economic Partnership (TPP), and Regional Comprehensive Economic Partnership (RCEP), respectively, to find the backward trade linkages between them instead of normal forward linkages.Design/methodology/approachTo calculate “a region” content in intermediate and value-added exports, this paper uses OECD’s inter-country input-output table (ICIOT), and tries to decompose the contents of trade. Using the information of ICIOT, Koopman et al. (2014) and Wang et al. (2013) decompose gross exports of a country’s exports.FindingsTPP is a loosely tied bloc featured by openness to the Asia-Pacific region. Trade linkages between members are stronger in RCEP than those in TPP, particularly in the trade of intermediate goods. Trades in RCEP are closely connected to exports to TPP, but the opposite direction is not clear.Research limitations/implicationsFirst of all, the recent base year of the data on value added in trade is 2011, which can be regarded as a little bit out of date. Therefore, it should be cautious in interpreting the results in that it may not reflect the characteristics of current trade. Second, this paper uses ICOIT instead of world input-output table.Practical implicationsA large portion of trades in RCEP and TPP is triggered by a global production network (fragmentation, vertical specialization), different from traditional trade focusing on inter-industry trade or competition between countries. Thus, the formation of TPP or RCEP is predicted to stimulate trade of the other instead of discriminating nonmember countries.Social implicationsIn particular, the authors have special concern in the backward linkages between RCEP and TPP, the distinct characteristics of the two regional blocs and, finally, major countries’ preferences of the one over the other and industrial conflicts toward TPP or RCEP even in an economy.Originality/valueAlthough this paper uses the approach by Baldwin and Lopez-Gonzalez, this paper is the first research on the analysis of the export contents in major trading blocs in the Asia-Pacific region.