Open Interest
FreeValueStandardPro
Fetch open interest history for an option contract.
- Open Interest is normally reported once per day by OPRA at approximately 06:30 ET.
- A new open interest message might not be sent by OPRA if there is no open interest for the option contract.
- The reported open interest represents the open interest at the end of the previous trading day.
rust
pub fn option_history_open_interest(
&self,
symbol: &str,
expiration: &str,
date: &str,
) -> OptionHistoryOpenInterestBuilder<'_>Optional parameters chain on the builder: .strike(&str), .right(&str), .max_dte(i32), .strike_range(i32), .start_date(&str), .end_date(&str). Execute with .await → Result<Vec<OpenInterestTick>, Error>, or decode chunk-by-chunk with .stream(handler).
Example
rust
let rows = tdx
.option_history_open_interest("SPY", "20250321", "20250303")
.strike("570")
.right("C")
.await?;
for t in &rows {
println!("date={} open_interest={}", t.date, t.open_interest);
}Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
symbol | string | yes | — | Ticker symbol (e.g. AAPL) |
expiration | date | yes | — | Expiration date YYYYMMDD |
date | date | yes | — | Date YYYYMMDD |
strike | string | no | * | Strike price in dollars as a string (e.g. 500 or 17.5). Use * for wildcard selection. |
right | string | no | both | Option side. Accepted values: call, put, both. |
max_dte | int | no | — | Maximum days to expiration |
strike_range | int | no | — | Strike range filter |
start_date | date | no | — | Start date YYYYMMDD |
end_date | date | no | — | End date YYYYMMDD |
timeout_ms | int | no | — | Per-request deadline in milliseconds. 0 means no deadline. |
Response
Rows of OpenInterestTick:
| Field | Type | Description |
|---|---|---|
ms_of_day | i32 | Milliseconds since midnight Eastern Time. |
open_interest | i32 | Total outstanding contracts. |
date | i32 | Trading date as a YYYYMMDD integer. |
Wildcard requests additionally populate expiration (YYYYMMDD), strike (dollars), and right ("C" / "P") on every row to identify the contract; on single-contract requests these are absent (None / null / undefined; the Rust and C rows carry the documented 0 / 0.0 / '\0' fills).