fsc-securities-product

fsc-securities-product

_{<a href="README.ko.md">한국어</a>}

금융위원회's 증권상품시세정보 — the Korea Exchange's daily numbers for every listed ETF, ETN and ELW, served through Korea's public data portal. Free, and the licence puts no restriction on what you do with it.

What you get

Reaches	apis.data.go.kr
Cost	free. 이용허락범위 제한 없음 — no restriction on use, commercial included
Approval	automatic, at both the development and the operating tier
Quota	10,000 calls a day on a development key; an operating key can ask for more
History	from 2020-01-02

/1160100/service/GetSecuritiesProductInfoService/getETFPriceInfo
/1160100/service/GetSecuritiesProductInfoService/getETNPriceInfo
/1160100/service/GetSecuritiesProductInfoService/getELWPriceInfo

All three take the same paging, date and identity filters — numOfRows, pageNo, resultType, basDt, beginBasDt, endBasDt, likeBasDt, likeSrtnCd, isinCd, likeIsinCd, itmsNm, likeItmsNm, beginVs, endVs, and range filters on volume, value traded and market cap. Where they differ is what each product has of its own:

	ETF	ETN	ELW
value filter	beginNav/endNav	beginIndcVal/endIndcVal	—
underlying	bssIdxIdxNm	bssIdxIdxNm	udasAstNm
rate filter	beginFltRt/endFltRt	beginFltRt/endFltRt	—

Every parameter above was read off the vendor's own OpenAPI document, which the portal page carries inline. The ETF operation was additionally checked against live responses; the other two were not, and that is the difference between them.

What one row carries

The four that matter are the ones a price feed does not have.

ETF nav · ETN indcVal	assets per unit. Against clpr this is the premium or discount
bssIdxIdxNm · bssIdxClpr	the underlying index by name and close. Against nav this is tracking. ELW names its underlying udasAstNm · udasAstClpr instead
ETF nPptTotAmt · stLstgCnt, ETN indcValTotAmt · lstgScrtCnt	net assets and units outstanding — fund size, and whether it is growing
trqu · trPrc	volume and value traded — liquidity

The rest is the ordinary shape: basDt, srtnCd, isinCd, itmsNm, mkp, hipr, lopr, clpr, vs, mrktTotAmt, and fltRt on ETF and ETN.

⚠️ The index name tells you what kind of index it is. bssIdxIdxNm carries the vendor's own suffix — S&P500 Yen Hedged Index(PR), S&P 500 Covered Call 1% OTM Daily Index(TR). A total-return index already contains the distributions its constituents paid; a price index does not. Any comparison between nav and bssIdxClpr means something different in the two cases, and this field is how you tell them apart without a second source.

What this is not

⚠️ **clpr is not adjusted.** It is the price that traded. A distribution or a split leaves a step in it, and neither nav nor indcVal is back-adjusted either — so no series here is a total return and none can be used for one without repair.

That was measured rather than assumed: over 260 sessions of 069500 the ratio clpr / nav stays inside ±0.5% and mean-reverts, with no level shift anywhere. nav is never back-adjusted by anybody, so a clpr that had been adjusted would have left a permanent step against it. None is there.

So this document is not where a trend signal comes from. It is where you find out whether the fund you are about to hold trades near its assets, tracks what it claims to track, and is big enough to trade. For adjusted prices, use a source that says it adjusts them.

There is no distribution endpoint — not here and not in any Korean public API we could find. What nav against bssIdxClpr gives you is detection: on a distribution the fund's assets fall and its price index does not, and the day stands out. That works well for a fund tracking a Korean index (over the same 260 sessions the daily deviation for 069500 has a standard deviation of 4.5bp, and three days past four sigma landed on the quarter-end distribution dates). It does not work for a fund tracking a foreign index, where the Korean close and the foreign close are hours and a currency apart — the same measurement on 360750 gives a standard deviation of 127bp and nothing stands out at all.

What you supply

A 공공데이터포털 service key. Get one at data.go.kr/data/15094806 — 활용신청 is approved automatically, so the key works immediately.

Aumos appends it as serviceKey and keeps it in the system keychain; no manager ever sees it. Until you enter it, this source refuses its own calls by name and stops nothing else.

⚠️ An error arrives on a 200. The HTTP status is not the answer — response.header.resultCode is, and 00 is the one that means it worked.