Open-Source Business Models

What actually counts as open source?#

The Open Source Definition requires ten things of a licence, not one. Beyond source availability it demands free redistribution, permission to create and distribute derived works, no discrimination against persons, groups, or fields of endeavour, licence portability with the software, no product-specificity, no restriction on other software, and technology neutrality. OSI maintains the list of approved licences. (OSI, The Open Source Definition; OSI, approved licences)

The three criteria that source-available licences usually fail are no discrimination against fields of endeavour, free redistribution, and no restriction on other software.

Be precise in your own materials. MongoDB submitted the SSPL to OSI and withdrew the submission in 2019; OSI has consistently stated that SSPL is not an open-source licence. (Percona, Is MongoDB Truly Open Source?) Calling a source-available product "open source" is a defensible business decision made indefensibly — the licence text, dependencies, trademarks, contributor agreements, and distribution method all matter, and this page is not legal advice.

Why does the licence choice matter commercially?#

Distribution can begin before a sales conversation. Developers evaluate, adopt, integrate, and advocate without a procurement cycle. That is genuine product-led growth, and it lowers technical trust barriers a proprietary vendor has to buy.

A permissive licence invites a well-funded operator to run your software. That is the trade, and it is the entire reason for the relicensing wave below. Copyleft, particularly AGPL, shifts the calculus without leaving the definition.

Community trust is a balance-sheet asset with no line item. Documentation, governance, security response, release quality, and honest licence communication drive adoption. A surprise relicensing or a deliberately crippled free edition destroys it faster than any price change in ordinary SaaS.

The relicensing episodes, and what they cost#

Two of the four relicensers later re-added an OSI-approved option — Elastic in 2024 and Redis in 2025 — and in both cases the fork had already accumulated maintainers, cloud distribution, and its own release cadence. (Elastic, Elasticsearch is Open Source, Again; Redis, Redis is now available under the AGPLv3; OpenTofu, OpenTofu Announces Fork of Terraform) The practical lesson for founders is not "never relicense." It is that a licence change is a one-way door on the community side even when it is reversible on the legal side.

How do you build the commercial model?#

1. Define the free value#

Specify precisely what a capable user can run, modify, and operate without paying. The free product must solve a coherent problem on its own. If it does not, it is a trial wearing a community project's clothes, and developers will say so publicly.

2. Choose a paid scarcity#

3. Build the conversion funnel#

commercial ARR = active organizations × qualified-use rate × paid conversion rate × ACV

Count organizations, not events. A qualified-use signal is something like production volume above a threshold, multiple collaborators, regulated data, or a request for centralized controls — not a download.

4. Test capture after community investment#

managerial contribution = paid ARR × gross margin − commercial acquisition cost − community-specific investment

Community engineering, events, and documentation usually sit in R&D or marketing in the statements, not cost of revenue. Include them here anyway, and label the result a managerial measure so nobody mistakes it for a GAAP figure.

5. Protect portability and trust#

Publish the licence, the edition boundary, the security policy, the roadmap process, the trademark rules, and the contribution terms. Measure external contributors, issue response time, upgrade adoption, and community-to-commercial conversion — without treating community members as unpaid leads.

Two public reference points. Elastic combines self-managed subscriptions with a managed cloud: fiscal 2026 revenue was $1,739.3m, of which $837.3m (48%) was Elastic Cloud, up from 46% in fiscal 2025, with a net expansion rate of about 112%. GitLab describes itself as built on an open-core model: fiscal 2026 revenue was $955.2m (+26%), subscription revenue $864.7m (+28%), and users contributed more than 6,500 merge requests during calendar 2025. (Elastic Q4/FY2026 results, 28 May 2026; GitLab fiscal 2026 Form 10-K) Their brands, installed bases, and licences differ; these are illustrations, not templates.

Worked example: does the funnel cover the community?#

A project has 50,000 active organizations. 3% show qualified production use; 12% of those buy at an ACV of $18,000.

qualified organizations = 50,000 × 3% = 1,500

paid customers = 1,500 × 12% = 180

new ARR = 180 × $18,000 = $3,240,000

At 82% gross margin, gross profit is $2,656,800. Commercial acquisition cost is $3,500 per converted customer, or $630,000. Annual community-specific engineering, events, and documentation cost $1,400,000.

managerial contribution = $2,656,800 − $630,000 − $1,400,000 = $626,800

Contribution per paid customer before the fixed community investment:

$18,000 × 82% − $3,500 = $11,260

break-even customers = $1,400,000 ÷ $11,260 = 124.3 → 125

Now break it. If paid conversion falls from 12% to 5%, you win 75 customers and $1.35m of ARR. Gross profit is $1,107,000, acquisition cost $262,500, and managerial contribution is −$555,500. The community did not fail; the funnel did.

The gross-margin assumption matters as much as the conversion rate. 82% suits a support-and-enterprise-licence mix. A managed-cloud business buys compute, so 65% is a more honest planning number — and at 65%, contribution per customer falls to $18,000 × 65% − $3,500 = $8,200 and break-even rises from 125 customers to 171. Decide which business you are in before you pick the margin.

Caveat: this model treats community investment as a fixed cost independent of adoption, which is only true over a narrow range. Support load, security response, and release engineering all scale with installed base — including the part that never pays.

Related concepts#

• SaaS — the recurring economics of the managed offering.
• API as a Product — commercializing hosted access when open distribution is the wrong shape.
• Managed Services — selling operation and assurance around complex software.
• Cloud Marketplaces — distributing a managed edition through committed cloud spend.
• Freemium Model — comparing a pricing tier with licence-based freedom.
• Product-Led Growth — the adoption motion an open licence enables.
• Moats — assessing whether community, ecosystem, and operations are durable advantages.

Sources#

1. Open Source Initiative, The Open Source Definition and the list of OSI-approved licences, accessed 13 August 2026. Source for the ten criteria and approval status.
2. Percona, Is MongoDB Truly Open Source? A Critical Look at SSPL. Source for MongoDB's October 2018 SSPL adoption, the 2019 withdrawal from OSI review, and OSI's position that SSPL is not open source.
3. Elastic, Elasticsearch is Open Source, Again, 29 August 2024, and Elastic licensing FAQ. Source for the 2021 move to SSPL plus the Elastic License, the AWS OpenSearch fork, and the 2024 addition of AGPLv3.
4. Elastic N.V., Elastic Reports Fourth Quarter and Fiscal 2026 Financial Results, 28 May 2026. Source for FY2026 revenue of $1,739.3m, Elastic Cloud of $837.3m (48%), and net expansion rate of ~112%.
5. OpenTofu, OpenTofu Announces Fork of Terraform, 2023. Source for the fork following HashiCorp's 10 August 2023 move from MPL 2.0 to BUSL 1.1, and OpenTofu's move under the Linux Foundation.
6. Redis, Redis is now available under the AGPLv3 open source license, 1 May 2025. Source for the March 2024 move from BSD to RSALv2/SSPLv1, the Valkey fork, and the addition of AGPLv3 with Redis 8.
7. GitLab Inc., fiscal 2026 Form 10-K (year ended 31 January 2026), filed March 2026. Source for the open-core description, FY2026 revenue of $955.2m, subscription revenue of $864.7m, and 6,500+ community merge requests in calendar 2025.
8. Apache Software Foundation, Apache License 2.0, and GNU Project, GNU General Public License v3. Primary licence texts for the permissive and copyleft families.