Tricky, guessing the ARPA team.

Yes, tricky. The "father of the Internet" is Vinton Cerf who co-authored RFC 675 Specification of Internet Transmission Control Program (link) which was published in December 1974. On January 1, 1983, TCP/IP protocols became the only approved protocol on the ARPANET. Between those two dates, some experiments were carried out connecting one or more networks with ARPANET.

Ceci n'est pas un seing.