Looks Goudy-inspired for the serif and possibly the sans as well.

I hope Pieter van Rosmalen, designer of the Latin portion of South Korea's road sign typeface (or Panno), and also the typo-geek, should help.

Hello Jo Seonghyeon,

I am afraid I can’t help you with this. I think the best way is to ask the designer. In the pdf you see an e-mailaddress: rionss@chol.com
Good luck!

Pieter

Dank je anyway. In fact, she has a twitter account (@rionns), but is inactive since early May this year. But I'll try anyway.

Here's the serif sample compared to Goudy Old Style in red.

Yeah, serif looks more like Goudy, except that capital Q. Now, what about sans?

No answer about the sans yet. Similar font, anyone?

I e-mailed Sandoll, the distributor of Go-un fonts. And returned mail said that the Latin and numeral portions were made with references to Garamond, Goudy, Times, etc. for batang/serif ones and Helvetica, Fedra Sans, Humania[sic, I guess?], etc. for dotum/sans ones.

I don't want to close this thread just with this. So let me ask something. We learned the serif ones are close to Goudy Old Style. Then, which Latin sans serif font is close to Go-un Hangul Dotum's Latin and numeral portions? Helvetica is unlikely. I guess it's one of those two remaining humanist sans serif fonts, but the shape of glyphs is slightly different from that of Fedra Sans. (Especially capital M, etc) Any ideas?

What happened with this? Did they in fact do something unethical?

hhp

I don't know. May be she was looking for some... inspiration...?

Would somebody like to tell Sandoll it's not OK?

hhp

So when they released Sandoll Neo series, they emphasised that they have officially licensed Guardian Sans for Gothic Neo1 and Lyon Text for Myeongjo Neo1. But I know, it's all bitter.