110 pieces of the Tsumini mokkan have the mark 'Goji' (meaning the captain of a trading ship) on them and the most of them have 'Goji shi' (items for the private use of Goji), suggesting that many private trading goods for merchants were included.
積荷木簡の中には「綱司」（交易船長の意）という字を記すものが110点あり、その多くは「綱司私」と記され、商人の私的交易品が多く含まれていたことが伺える。