Documentation

ticker - the ticker (symbol) of the ETF
dt - the as of date as specified on the issuer's website (ISO 8601 format)
holdings - the issuer's BTC holdings
change - the change in holdings compared to the prior day
notes - notes on any calculation performed to arrive at holdings
update_ts - update timestamp in UTC (ISO 8601 format)
error - whether there was an error loading current data. If true, data is returned from the last successful day.

Data for Supported ETFs

Ticker	Description	Holdings	Change	Change %	As of Date	BT
ARKB	ARK 21Shares Bitcoin ETF	44,255	+348	+0.79	2025-09-17	BT
BITB	Bitwise Bitcoin ETF	40,907	-92	-0.22	2025-09-15	BT
BTC	Grayscale Bitcoin Mini Trust ETF	47,176	+52	+0.11	2025-09-16	BT
BTCC	Purpose Bitcoin ETF	20,624	+10	+0.05	2025-09-16	BT
FBTC	Fidelity Wise Origin Bitcoin Fund	207,543	+392	+0.19	2025-09-16	BT
GBTC	Grayscale Bitcoin Trust ETF	177,945	-7	-0.00	2025-09-16	BT
IBIT	iShares Bitcoin Trust ETF	763,699	+1,793	+0.24	2025-09-16	BT