---
title: "What we said on a date about the law on another"
method: GET
path: "/v1/rules/as-of"
tags: ["rules history"]
---

# What we said on a date about the law on another

`GET /v1/rules/as-of`

## Request

- Base URL: `https://tektolo.com` (the document declares no server; this is the origin it was published from)
- URL: `https://tektolo.com/v1/rules/as-of`
- Auth: none declared

The ruleset we served at ``known`` and the rule's value in it; with ``valid``, also
the dated version of the rule in force that day (from the rule's amendment history).
``ruleset`` is null when nothing indexed was served at ``known``.

## Query parameters

- `rule` string, required: A rule ID (deposit-settlement/states/CA#return) or a prefix of one (deposit-settlement/states/CA covers every rule area of California's row).
- `known` string, required: When we answered: a date (the end of that day, UTC) or an ISO time.
- `valid` string, nullable: The day the law applied to (YYYY-MM-DD).

## Response `200`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/tektolo/apis/tektolo-capabilities-api.md) · [All operations](https://skmtc.dev/tektolo/apis/tektolo-capabilities-api/llms.txt) · [OpenAPI document](https://skmtc.dev/tektolo/apis/tektolo-capabilities-api/revisions/6e667aa7b6f7?raw)