3.1 Intellectual Property: Copyright, Open Source, and Creative Commons
Key Takeaways
- Copyright protects the expression of an idea (source code, text, images), not the underlying idea or algorithm, and it exists automatically once a work is fixed in a tangible form.
- In the United States, copyright generally lasts for the author's life plus 70 years; a utility patent generally lasts 20 years from the filing date.
- Permissive licenses such as MIT, BSD, and Apache 2.0 allow reuse in closed-source products; copyleft licenses such as the GNU GPL require distributed derivative works to use the same license.
- The Creative Commons Attribution (CC BY) license allows copying, adaptation, and commercial use as long as the creator is credited as the license specifies.
- Fair use is judged case by case on four factors: purpose and character of the use, nature of the work, amount used, and effect on the market.
What this competency asks
ETS asks you to know different methods of protecting intellectual property rights and the trade-offs between them in a variety of contexts, and it names Creative Commons, open source, and copyright as examples. You should be able to:
- Use correct vocabulary to describe how each method works.
- Given a context, identify an appropriate method.
- Identify and compare the trade-offs between methods.
The four legal forms of intellectual property
Intellectual property (IP) is a creation of the mind that the law lets its owner control.
| Form | Protects | How you get it | Duration (U.S.) | Software example |
|---|---|---|---|---|
| Copyright | Original expression fixed in a tangible form | Automatically, when the work is created | Life of the author + 70 years; works made for hire: 95 years from publication or 120 from creation, whichever ends first | Source code, documentation, game art |
| Patent | A new, useful, non-obvious invention or process | Application and examination by the USPTO | 20 years from the filing date (utility patents) | A novel technical method |
| Trademark | Names, logos, and slogans that identify the source of goods or services | Use in commerce; registration strengthens rights | As long as it is used and defended | A product name or logo |
| Trade secret | Valuable information kept secret | Reasonable secrecy measures such as NDAs and access controls | As long as it stays secret | A proprietary recommendation formula |
Key distinctions
- Idea versus expression. Copyright covers the specific code a programmer wrote, not the algorithm it implements. Someone else may independently write different code for the same algorithm. A patent, when one is granted, can protect a functional method, even against someone who invented it independently.
- Registration. Copyright exists without registration. For U.S. works, however, registration is required before you can sue for infringement, and timely registration makes additional remedies available.
- Trade secrets end when the secret gets out through leaks, independent discovery, or lawful reverse engineering.
Fair use
Fair use (17 U.S.C. § 107) permits limited use of copyrighted material without permission for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Courts weigh four factors case by case:
- Purpose and character of the use. Is it nonprofit or educational? Is it transformative, adding new meaning or a new purpose?
- Nature of the copyrighted work. Factual works are more open to fair use than highly creative ones.
- Amount and substantiality of the portion used, including whether it is the "heart" of the work.
- Effect on the market for the original. Does the use substitute for a sale?
An educational purpose helps but does not automatically make a use fair. Copying an entire workbook for every student each year harms the market for the workbook. In Google LLC v. Oracle America (2021), the U.S. Supreme Court held that Google's copying of roughly 11,500 lines of Java API declaring code to build a new platform was fair use. The Court stressed that the use was transformative and relied on functional interface code.
The DMCA
The Digital Millennium Copyright Act (1998) added two rules that matter in computing:
- Anti-circumvention (Section 1201): It is generally illegal to bypass technical protection measures (digital rights management, or DRM) that control access to copyrighted works. The Librarian of Congress grants limited exemptions in a rulemaking every three years.
- Safe harbor (Section 512): Online service providers are protected from liability for users' infringing uploads if they meet conditions, including removing material promptly after a valid takedown notice.
Open-source licenses
Open-source software makes its source code available under a license that allows use, study, modification, and redistribution. The author still owns the copyright; the license grants permissions.
| License | Type | Commercial use | Must share source of distributed derivatives? | Notes |
|---|---|---|---|---|
| MIT | Permissive | Yes | No | Keep the copyright and license notice |
| BSD (2- or 3-clause) | Permissive | Yes | No | Similar to MIT |
| Apache 2.0 | Permissive | Yes | No | Includes an explicit patent license |
| GNU GPL (v2, v3) | Strong copyleft | Yes | Yes, under the same license | "Share-alike" for code |
| GNU LGPL | Weak copyleft | Yes | Only changes to the library itself | Designed for libraries |
| GNU AGPL | Network copyleft | Yes | Yes, including when the software is offered as a network service | Closes the "run it on a server" gap |
- Permissive licenses maximize adoption. A company can use the code in a closed-source product.
- Copyleft licenses keep improvements open. If you distribute a program that incorporates GPL code, you must release the combined program's source under the GPL.
- Open source is not the same as free of obligations. Every license has conditions, even if the only one is keeping a notice.
Creative Commons
Creative Commons (CC) licenses let creators pre-grant permissions for works such as text, images, audio, video, and lesson materials. Creative Commons itself recommends software-specific licenses for code. Licenses combine these elements:
| Element | Meaning |
|---|---|
| BY (Attribution) | Credit the creator in the manner the license specifies |
| SA (ShareAlike) | Adaptations must use the same license |
| NC (NonCommercial) | No commercial use |
| ND (NoDerivatives) | Share only unchanged copies |
The most permissive license, CC BY, allows copying, adaptation, and commercial use as long as attribution is given. CC0 is a public-domain dedication in which the creator waives rights as far as the law allows. A work in the public domain, whether its copyright expired or it was never protected, can be used by anyone for any purpose.
ETS's sample question on this topic describes a programmer who uses CC BY–licensed code in a commercial product. The acceptable use is copying the code and crediting the author as the license indicates. Changing variable names, or limiting the copy to a few lines, does not satisfy or replace the attribution requirement.
Trade-offs at a glance
| Method | Advantage for the creator | Cost or limitation |
|---|---|---|
| All rights reserved (default copyright) | Maximum control; can sell licenses | Others cannot legally reuse or build on it without permission |
| Patent | Strong protection for a functional method | Expensive, slow, public disclosure required, limited term |
| Trade secret | No expiration, no disclosure | Lost if leaked or reverse-engineered |
| Permissive open source | Wide adoption, community contributions | Others may build closed products on your work |
| Copyleft open source | Improvements stay open | Some companies avoid it because of the sharing obligation |
| Creative Commons | Clear, easy reuse terms for educators and artists | NC and ND options restrict remixing; licenses cannot be revoked for copies already shared |
In the classroom
Teachers model IP practice. Cite the sources of images and code. Choose CC-licensed or public-domain media for student projects. Teach students to read a license before reusing code from the Internet. Explain that finding something online does not make it free to use.
A student wants to use a photograph licensed under CC BY in a poster that will be sold at a school fundraiser. What must the student do?
A startup wants to include an open-source library in a proprietary app that it will distribute without releasing the app's own source code. Under which license would that plan violate the license terms?
A programmer independently writes new code that implements the same sorting algorithm used in a competitor's copyrighted program without copying any of the competitor's code. Which statement is correct?