Architecture and Hardware Legally speaking

Copyright Implications of Emulation Programs

How emulation programs might be affected by new claims of copyright infringement.
  1. Introduction
  2. The SAS v. WPL Lawsuits
  3. History of Software Emulations
  4. Copyright Challenges to Software Emulations
  5. SAS's Latest Appeal
  6. Conclusion
  7. Author
isometric drawing of cubes

Thrice has SAS Institute tried to persuade courts that World Programming Ltd. infringed copyright in its widely used statistical analysis program by emulating the SAS program's functionality. WPL designed its directly competing program to emulate the SAS functionality so that people who wrote programs in the SAS Language for various statistical procedures would be able to execute those programs on WPL's platform if they chose to switch from SAS's software to WPL's. SAS's latest appeal of an unfavorable ruling is now pending before the Court of Appeals of the Federal Circuit (CAFC).

After describing the three SAS v. WPL lawsuits, this column gives examples of emulation programs that have either not encountered or overcome copyright lawsuits. It then explains why there is reason to worry that SAS's latest lawsuit might succeed.

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The SAS v. WPL Lawsuits

SAS filed its first lawsuit against WPL in the U.K., where WPL is based. That lawsuit claimed that WPL infringed by copying the functional behavior of SAS's software, the SAS programming language, and program interfaces. SAS argued that these elements of its software are original and creative and therefore copyright-protectable. After the Court of Justice of the European Union (CJEU) ruled these elements are not within the scope of protection that E.U. copyright law affords to computer programs, a U.K. court resolved this dispute in WPL's favor.

It is relatively common for software developers to emulate the functionality of an existing computer program.

Unsatisfied with the U.K. ruling, SAS brought a new lawsuit against WPL in North Carolina. A trial court rejected SAS's copyright claim because it perceived SAS to be seeking copyright protection over software language functions that SAS had conceded were freely usable by programmers of the SAS Language. Similarities between the SAS and WPL programs' outputs, it said, established only that "when defendant's software compiles and interprets SAS Language programs' input by users, it does so properly." Consequently, the court ruled in WPL's favor.

SAS appealed the adverse N.C. copyright ruling, but that appeal failed. The appellate court upheld a damage award against WPL under a different legal theory. Finding it unnecessary to address SAS's copyright claim, the appellate court vacated the lower court's copyright ruling.

Because the N.C. ruling was vacated, SAS filed a new copyright infringement lawsuit against WPL, this time in a federal court in Texas. That complaint included a patent infringement claim, as a result of which SAS knew the CAFC would hear any appeal in the case. That lawsuit claims that WPL copied the input and output formats of the SAS program. It chose Texas because a 1990s appellate court ruling in that jurisdiction had held that input and output formats of computer programs, if sufficiently original, could be copyrighted.

A Texas trial court judge held a hearing to consider whether SAS had shown that WPL had copied some copyrightable elements of the SAS program. This was in keeping with a widely used "abstraction, filtration, comparison" (AFC) test for software copyright infringement. That test requires courts to "filter" out of consideration various types of unprotectable elements in software copyright cases before sending an infringement case to a jury.

WPL's expert offered numerous reasons why various elements of the SAS software (for example, the SAS Language) should be filtered out. SAS's expert resisted doing any filtration, saying that WPL copied original elements of the SAS software and so the case should go to a jury. The trial judge dismissed SAS's claim for failure to show the elements it claims WPL copied were copyright-protectable.

SAS has appealed this dismissal to the CAFC. This is, of course, the court that ruled against Google in the Oracle case that challenged Google's reimplementation of parts of the Java Application Programming Interface (API) in Android. SAS smartly hired one of Oracle's lead lawyers in the Oracle case to handle the SAS appeal.

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History of Software Emulations

It is relatively common for software developers to emulate the functionality of an existing computer program. This practice has generally been regarded as legitimate, socially beneficial, and consistent with U.S. copyright's constitutional fair balancing of the interests of first-generation creators, on the one hand, and those of follow-on innovators, on the other.

One of the earliest and most famous examples was Phoenix Technologies' reimplementation of the IBM PC's BIOS (Basic Input-Output System) that enabled the PC revolution. Phoenix carefully documented its "clean room" development process to prevent from IBM complaining that it copied any IBM code. IBM may not have been happy about what Phoenix did, but it did not sue Phoenix for infringement.

Open source as well as proprietary software developers often emulate the functionality of existing programs without incurring legal troubles. This enables software markets to be more competitive. Emulation programs often introduce new innovative features. Consumers benefit from both the competition and innovation that emulation programs can provide.

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Copyright Challenges to Software Emulations

Some software developers have tried to thwart competitive emulations by claiming they infringe copyrights. So far, courts have rebuffed these claims and allowed follow-on creators to build competing software that reimplements functionality and to reuse unprotectable elements of other entities' software.

For example, Sony once sued Connectix for infringement because it developed software that emulated much of the functionality of Sony's PlayStation platform. Users of Connectix's software could play games designed to run on the Sony platform on their PCs instead. Sony's lawsuit claimed Connectix infringed by making copies of the Sony platform software in the course of reverse-engineering it to figure out how the PlayStation software was configured. The court rejected Sony's claim on fair use grounds. It recognized Sony's lawsuit was aimed at preventing legitimate competition. In effect, Sony sought to thwart reuse of unprotectable, functional elements of the PlayStation software.

Another example is Bateman v. Mnemonics. Mnemonics developed an application program that automated parking garage operations. That program was designed to run on Bateman's operating system (OS) program. After a falling out, Bateman cancelled the OS license with Mnemonics. To preserve its business, Mnemonics developed an OS program on which it could run its application. Bateman alleged the new OS infringed its OS copyright.

Although a trial court ruled that Mnemonics infringed because its new OS contained some code from the Bateman program, an appellate court reversed the infringement ruling. Mnemonics convinced that court that the copying was necessary to enable the new OS to be compatible with the application program for which it was developed.

The most analogous case to SAS v. WPL, however, is Lotus v. Borland. Borland's Quattro Pro spreadsheet software directly competed with Lotus 1-2-3. Borland's program had two user interface modes. One was a "native" interface that Borland's engineers had designed; the other was an "emulation" interface to enable users experienced with Lotus 1-2-3 to run on Borland's platform the macros they had created in the Lotus macro language to execute common sequences of functions.

Because Quattro Pro's emulation interface reproduced the Lotus command hierarchy, Lotus sued Borland for copyright infringement. Borland defended the lawsuit by claiming the command hierarchy was unprotectable by copyright law. Borland said it was necessary to display exactly the same commands in exactly the same order as 1-2-3 to enable user-created macros to run on Borland's platform.

A trial court ruled Borland was an in-fringer because Lotus had been creative in selecting and arranging the commands. Hence, they were original expressions, not unprotectable ideas.

Open source as well as proprietary software developers often emulate the functionality of existing programs without incurring legal troubles.

An appellate court reversed this ruling, having been persuaded the Lotus command hierarchy constituted an un-protectable method of operating a spreadsheet program. The ruling was consistent with a late 19th century Supreme Court case, Baker v. Selden, in which the Court ruled that the selection and arrangement of columns and headings for bookkeeping forms were un-protectable as constituent elements of Selden's novel bookkeeping method.

Lotus asked the Supreme Court to review the ruling in Borland's favor. Although the Court agreed to hear Lotus' appeal, the Justices deadlocked 4-4 on the merits. (When there is a 4-4 split, the Supreme Court affirms the appellate court's ruling, but without setting a precedent on the merits of the claim.)

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SAS's Latest Appeal

SAS's latest appeal parallels Oracle's main argument to the CAFC in Oracle v. Google. Oracle asserted the Java API declarations and the structure, sequence, and organization (SSO) of the Java API are original expression (and hence copyright-protectable) because they are creative and one of many alternative ways to name the declarations and structure the API. (I believe this argument is fallacious, but the Supreme Court did not reverse it in its Google v. Oracle decision last April.)

SAS's latest appeal reiterates the same core argument to the CAFC as Oracle made in 2014: The input and output formats of the SAS program SAS says WPL copied are original expressions because SAS made many creative choices about how to design the formats.

SAS also argues the registration certificates it received from the Copyright Office provide it with a presumption all elements of its software are original expressions; it claims WPL bears the burden of proving the copied elements are unprotectable under specific copyright doctrines. SAS argues WPL failed to do this.

WPL has asked the CAFC to affirm the lower court's dismissal of SAS's complaint, arguing that the trial court properly filtered out many unprotect-able elements of the SAS software, including the SAS Language and the functional behavior of the SAS program.

An intellectual property law scholars' amicus curiae brief, of which I am a coauthor, supports WPL's arguments. It points out numerous flaws in SAS's arguments. It invokes the Supreme Court's 2021 Google v. Oracle decision (which cited positively to the Borland decision four times) that rejected Oracle's claim of infringement because of the creativity Google's reuse of the API unleashed. The Court took note of the heavy investments Java programmers had made in learning the Java API declarations and in creating new apps with them.

Google is relevant because the district court's decision in SAS helps unlock WPL's and other parties' creative energies, consistent with copyright law's ultimate objective of promoting, rather than hindering, ongoing creativity. WPL should be commended for enabling those who developed programs in the SAS Language to continue to use those programs on a different platform if they so choose.

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One can only hope the CAFC will critically analyze whether SAS's input-output claims against WPL are an indirect attempt to extend copyright protection to the SAS Language and the functionality of the SAS program, contrary to sound precedents. A ruling in SAS's favor would undermine the legitimate interests of SAS Language users to enjoy the fruits of their socially beneficial creations on the platform of their choice.

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