BSL Guide

SPDX Identifier: BUSL-1.1 (also referred to as BSL-1.1)

What Is BSL?

BSL (Business Source License) is a license created by MariaDB Corporation in 2013. Its core characteristic is that it is a time-limited license.

How It Works

1. Initial period (before the Change Date)

   • Certain commercial uses are restricted
   • The source code is publicly available
   • Non-commercial/internal use is generally permitted

2. Conversion period (after the Change Date)

   • Automatically converts to a true open source license
   • Usually converts to Apache-2.0, GPL-2.0, MIT, etc.
   • All restrictions are lifted

The Three Main Parameters of BSL

1. Additional Use Grant

Specifies the particular uses that are permitted.

Examples:

• “Services with 1,000 or fewer annual users are permitted”
• “Free use is allowed in non-production environments”
• “Use for the purpose of providing a competing service is prohibited”

2. Change Date

The date on which it converts to open source. Typically set to 3-4 years after release.

Example: If released on January 1, 2024, the Change Date is January 1, 2028.

3. Change License

The open source license it will convert to.

Typically:

• Apache-2.0 (most common)
• GPL-2.0
• MIT

Major Projects Adopting BSL

Databases

• MariaDB (some features): Change License GPL-2.0, Change Date 4 years after release
• CockroachDB: Change License Apache-2.0 or MIT, Change Date 3 years after release

Others

• Ceph (some features)
• MinIO (some editions)
• Sentry (some features)
• Akka (since 2.7)

Determining Whether Use Is Permitted

Cases Generally Permitted

1. Internal development/testing

   • In-house development environments
   • Test servers
   • Prototype development

2. Non-production uses

   • Learning/research
   • Benchmarking
   • Proof of Concept (PoC)

3. Cases specified in the Additional Use Grant

Cases That Are Restricted

1. Commercial production use

   • Services provided to customers
   • Inclusion in and sale of a product
   • Provision as SaaS

2. Providing a competing service

   • Providing a service that competes with the BSL software

Cases Requiring Verification

Because the Additional Use Grant differs for each project, checking the LICENSE file of each project is essential.

Use After the Change Date

Once the Change Date passes, it automatically converts to the Change License.

Example: CockroachDB v20.1 (released May 2020)

• Change Date: May 19, 2023
• Change License: Apache-2.0
• From May 19, 2023, it can be used freely under Apache-2.0

References

• BSL 1.1 Full Text
• SPDX License List - BUSL-1.1
• MariaDB BSL FAQ
• CockroachDB Licensing FAQs