Registered to FileMaker as its Administration Server access port.
IANA lists 16000 as fmsas, "Administration Server Access", registered by FileMaker (now Claris), which pairs it with 16001 (fmsascon) and the 16020/16021 Java Web Publishing ports. Historically the FileMaker Server Admin Console was reached at https://host:16000; current versions front the console on 443 and keep 16001 for local access. Because the number is convenient and unpoliced, other software squats it too, so confirm what answers before assuming FileMaker.
Do not expose
An administration plane for a database server. If it is really FileMaker's admin service, it belongs on a management network, not on a public IP.
$ curl -skI --max-time 5 https://TARGET:16000/Seen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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