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Embraer and Trans States Sign Deal for up to 100 E175-E2s

http://www.embraer.com.br/en-us/imprensaeventos/press-releases/noticias/pages/embraer-e-trans-states-assinam-acordo-para-ate-100-e175-e2.aspx

The order, which is valued at approximately USD 2.4 billion at list
prices, is subject to certain conditions. It will be added to the
Company's firm order backlog when these conditions are met and final
confirmation of the aircraft is received from Trans States.

やはり
"The order, ... , is subject to certain conditions."
で条件付注文