application/vnd.ms-fontobject

Embedded OpenType, Microsoft's proprietary web font wrapper from the Internet Explorer era — submitted to the W3C in 2008 but never standardized, and superseded by WOFF everywhere. The only reason to serve one today is supporting IE 8 or older, which no longer justifies the bytes; drop it from @font-face stacks and ship WOFF2. Unusually, its magic number is not at the start of the file: the two bytes reading LP sit at offset 34, after the size and version fields, which is exactly how the WHATWG sniffing algorithm identifies it.

Defined by W3C Member Submission — Embedded OpenType (EOT) File Format · IANA registration. Registry facts from the IANA media-types registry via mime-db.