Is Open Source a “Public Good”?

I’ve sat through a fair number of conference presentations about open source in which the speaker alludes to that fact that open source is a “public good”.   Everyone nods, people pat themselves on the back, but few dig into the meaning of the words.  Unless we dig into the meaning of this word, I think we’re missing something important.

What is a “Public Good”?

Your economics textbook will tell you that a public good is one that is both nonrival and non-excludable.   In simpler terms, your use of a public good does not decrease the availability of a good for others (nonrival) and no one can be effectively excluded from consuming a public good (non-excludable).   Wikipedia uses air as an example:

“breathing air does not significantly reduce the amount of air available to others, and people cannot be effectively excluded from using the air. This makes air a public good”

Once you learn about public goods, you learn about private goods which are (rival and excludable).   My Lamborghini* is a private good.  When I purchased that car it meant that there was one less Lamborghini available for you (rival) and you clearly don’t have enough money to purchase such a car (excludable).  Easy right?   Quiz yourself, “Air… public.   Your MacBook Pro… private.  Apache httpd… public.   Microsoft Office… private”.  Except there are two more types of goods.

Two Other Types of Goods: Club and Common

Club goods are nonrival but excludable.   Examples (again from Wikipedia) are cable TV and iTunes.   In these situations, if it weren’t for some factor allowing for exclusion, these goods could be considered public goods.  Take cable TV as an example, if Cable TV were freely available, it would be considered a public good.    Instead, Cable TV, like Microsoft Windows or the latest Usher album is a Club Good.   You are excluded from consumption if you haven’t paid the price of the software (or the price of admissions).

A “common good” is rival but non-excludable.  There is a limited supply of a Common Good, consuming this resource makes it less available for everyone else, and there are no effective mechanisms for excluding access to these goods.   Forests, natural resources, clean air, etc.   Anything finite that we all have access to.   Again with Wikipedia, an example of a Common Good: “fish stocks in international waters; no one is excluded from fishing, but as people withdraw fish without limits being imposed the stocks for later fishermen are potentially depleted” 

What is Open Source?

Back to the question “Is Open Source a Public Good?”   I think the question focuses too much on the end-product of Open Source as being “software”, be it Apache httpd, Linux, most people tend to focus on the deliverable output – a CD containing the kernel or a tarball containing httpd.   If this is your definition of a “good” for open source, then, yes, a TGZ distribution of Apache httpd is both nonrival and non-excludable (therefore public).   From my perspective, this is the wrong “good” to focus on, the real value of an open source product isn’t the end product. 

Focusing on the software artifact is the mistake.    Yes, the source code and the binary are a public good, but this is just the tip of the iceberg.   What then are the real “goods” in an open source?

  • The Attention of Core Developers (Private Good)
    • Direct private participants like Redhat, Springsource, and Amazon all depend upon Tomcat in some form, the pay contributors to contribute features and maintain the projects directly.
  • Participation in a Community (Club Good)
    • There is a cost to participating in an open source community.  That cost (to an organization) is an often sizable investment in both infrastructure and support costs for the underlying community.  Individuals who participate in a particular open source project, who are granted access to make code modifications are almost always expected to make a significant payment in the form of both effort and attention. 
  • Support for a Project (Private Good)
    • If you’ve used open source in a production environment, you’ll understand that there is no avoiding this cost.  Either you pay your internal development staff to “support” open source infrastructure, or you end up paying a vendor.
  • Documentation (Club Good)
    • Why a club good?  Many projects tend to publish documentation with a publisher (like O’Reilly), in these situations the documentation can very easily be understood as a Club Good.   If a company sponsoring an open source project makes documentation available as an open source artifact, it is often very common for that company to attach a cost (in the form of registration) to access this documentation.

You could also consider the attention of the Community itself as “Common Good” (one that is both rival and non-excludable).  In a truly open project, anyone can show up, and with very little restriction they can choose to interact with and “consume” the attention of the community as they choose.

Understanding Open Source as a Hybrid of Competing “Goods”

While there has been a fair amount of research characterizing open source as either a public good or a complex public good [Bessen 2005], I don’t think anyone has challenged the assertion that open source communities are engaged in an effort to create public goods.   The problem with the industry is we’re only appreciating open source as either a public good or a private good.   In other words, most businesses tend to think of open source as either a public good (read irrelevant) or a private good (read relevant).   They fail to understand that, they are, in effect, stewards of a community and managers of the intersection of a complex assembly of different “goods”.

Next time someone tells you that open source is a “public good”, tell them to jump in a lake.  What they consider a “public good” is only the tip of the iceberg.

Bessen, James E., Open Source Software: Free Provision Of Complex Public Goods (July 2005). Available at SSRN: or doi:10.2139/ssrn.588763

*Note: I don’t own a Lamborghini, I was just using this as a hypothetical.