---
title: "Per-symbol OI change series"
method: GET
path: "/options-flow/oi-changes/{symbol}"
tags: ["Derived Analytics"]
---

# Per-symbol OI change series

`GET /options-flow/oi-changes/{symbol}`

## Request

- Base URL: `https://optionsbell.com/api/v1`
- URL: `https://optionsbell.com/api/v1/options-flow/oi-changes/{symbol}`
- Auth: API key in header `X-API-Key`

One symbol's total / call / put open interest per trading day with
the change versus the previous day with data, newest first. The
oldest row in the window has no predecessor, so its `prev_*` and
`*_change` fields are null. `date` in the envelope is the newest day
returned.

## Path parameters

- `symbol` string, required

## Query parameters

- `date_from` string, date
- `date_to` string, date
- `limit` integer

## Response `200`

OI change series

- object
  - `symbol` string, required
  - `date` string, date, nullable, required
  - `date_from` string, date, nullable, required
  - `date_to` string, date, nullable, required
  - `count` integer, required
  - `data` OiChangeSeriesRow[], required
    - `date` string, date
    - `prev_date` string, date, nullable
    - `total_oi` string: Numeric string.
    - `prev_oi` string, nullable: Numeric string.
    - `oi_change` string, nullable: Numeric string.
    - `oi_change_pct` number, nullable: Fraction (0.5 = +50%); null when prev_oi is 0 or missing.
    - `call_oi` string: Numeric string.
    - `prev_call_oi` string, nullable: Numeric string.
    - `call_oi_change` string, nullable: Numeric string.
    - `put_oi` string: Numeric string.
    - `prev_put_oi` string, nullable: Numeric string.
    - `put_oi_change` string, nullable: Numeric string.

## Other responses

- `400`: Invalid input: `INVALID_SYMBOL`, `INVALID_DATE`, `INVALID_DATE_RANGE`, `INVALID_PARAM`.
- `401`: Missing or invalid API key: `MISSING_API_KEY`, `INVALID_API_KEY_FORMAT`, `INVALID_API_KEY`. No rate-limit headers.
- `403`: Key is valid but has no usable subscription: `NO_ACTIVE_SUBSCRIPTION` (no Personal plan on the key) or `SUBSCRIPTION_INACTIVE` (past due, paused, expired, or canceled past its period end). No rate-limit headers.
- `429`: Rate limit exceeded: `RATE_LIMIT_MINUTE` (60/min) or `RATE_LIMIT_DAY` (4,000/day). Carries both rate-limit header sets and `Retry-After` (seconds until the exhausted window opens again). Rejected requests count against the minute window, so back off instead of retrying immediately.
- `500`: Unexpected server error: `INTERNAL_ERROR`. The body and the X-Request-Id header carry the request id.
- `503`: Authentication backend unreachable: `AUTH_UNAVAILABLE`. Retry later. No rate-limit headers.

---

[API](https://skmtc.dev/optionsbell/apis/optionsbell-options-flow-api.md) · [All operations](https://skmtc.dev/optionsbell/apis/optionsbell-options-flow-api/llms.txt) · [OpenAPI document](https://skmtc.dev/optionsbell/apis/optionsbell-options-flow-api/revisions/42db9bcaa61f?raw)