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## \[V3 REST API] Unified API, New Stability Guidelines, and Breaking Changes

### Overview

We are releasing a set of significant updates to the V3 REST API, including a unified API spec, new stability guidelines, and several new features. **This release includes breaking changes.** Please review the migration details below carefully.

### Breaking Changes

> **Migration timeline**
>
> The following changes will become available on **June 15**. You have 90 days to migrate off the legacy paths.

#### Unified API spec at `/v3/`

The `v3-alpha` and `v3-beta` routes are being deprecated. The entire API spec is now unified under `/v3/`. Going forward, beta endpoints are accessible from the same `/v3/` base path by including the `EARLY-ACCESS: true` header in your request.

**Migration:** Update your base URL to `/v3/`, which uses a cleaner spec — object names no longer carry the `benchling.` prefix and URLs no longer carry the `/benchling` prefix. To continue accessing beta endpoints, add an `EARLY-ACCESS: true` header.

#### Updated stability guidelines

We have updated our stability guidelines for the V3 API. The key changes are:

|                        | **stable**      | **beta**  |
| ---------------------- | --------------- | --------- |
| Breaking change window | >90 days notice | No notice |

Beta endpoints (accessed via `EARLY-ACCESS: true`) may change at any time without notice. Stable endpoints will receive a minimum of 90 days notice before any breaking change. [Read the full stability guidelines →](/docs/stability-guidelines)

### ✨ New Features

#### Batch Create/Update APIs

A more efficient way to update multiple items in a single request, without the file-based approach required by our Bulk APIs. Batch Create and Batch Update are enabled by default on all write endpoints. [See an example: Custom Entity Batch Create →](https://benchling.com/api/v3/reference#/CustomEntity/CustomEntity.BatchCreate)

#### Returning and Omit parameters

Developers can now control exactly which fields are returned on all list and get endpoints. Specify `returning` to include specific properties, or `omit` to exclude them. The two lists must be mutually exclusive. [Learn more →](/docs/changelog/2026/5/21)

#### New (beta) APIs

New Entity Schema APIs, results bulk write APIs, and Audit Logs APIs are now available for testing in `v3-beta` (and after June 15, via the `EARLY-ACCESS: true` header).

---

### Migration Checklist

* [ ] On June 15, update the base URL from `/v3-alpha/` or `/v3-beta/` to `/v3/`

* [ ] Add `EARLY-ACCESS: true` header to any requests targeting beta endpoints

* [ ] Review the [updated stability guidelines](/docs/stability-guidelines)

Questions or feedback? Reach out in the [Benchling Community](https://community.benchling.com/) or via your account team.