## Facts

- Caldera, as successor to DR-DOS-related antitrust claims, sued Microsoft alleging exclusionary conduct designed to protect Microsoft’s dominance in PC operating systems and suppress DR DOS as a competing DOS product.
- The complaint asserted claims under Sherman Act §§ 1–2 and Clayton Act § 3 based on a pattern of allegedly anticompetitive practices affecting OEM and consumer adoption of DR DOS.
- Microsoft sought partial summary judgment on several sets of theories; the decision addressed motions targeting claims based on (1) perceived incompatibilities, (2) intentional incompatibilities, (3) predisclosure/beta-testing exclusion, and (4) technological tying through Windows 95’s integration of DOS and Windows functionality.
- Caldera presented evidence that Microsoft used product messages, design choices, and related communications to create or exploit a perception that DR DOS was incompatible with Windows, and that some incompatibilities were intentionally created or used to disadvantage DR DOS.
- Caldera also alleged Microsoft excluded DR DOS from Windows beta programs and early technical information to impair DR DOS’s ability to interoperate with Windows and to advantage Microsoft’s own DOS products.
- As to Windows 95, Caldera alleged Microsoft combined products previously sold separately (DOS and Windows) in a manner that foreclosed DR DOS and maintained Microsoft’s operating-system monopoly, functioning as an unlawful tying arrangement not justified by consumer-benefiting efficiencies.
- Caldera moved to strike Microsoft’s partial-summary-judgment briefs; the court addressed that request alongside the merits.

## Issues

1. Whether evidence regarding perceived incompatibilities and intentional incompatibilities between Windows and DR DOS could permit a finding of exclusionary conduct rather than legitimate product design or truthful technical warnings.
2. Whether Microsoft’s alleged exclusion of DR DOS from beta testing and predisclosure of technical information could support monopolization or restraint-of-trade theories, or was insulated as ordinary discretion over pre-release information sharing.
3. Whether Windows 95’s integration of DOS and Windows could constitute unlawful technological tying or exclusionary conduct under Sherman Act §§ 1–2 and Clayton Act § 3, or instead was immune as a permissible product improvement as a matter of law.
4. Whether Caldera’s motion to strike Microsoft’s partial-summary-judgment briefing should be granted.

## Decision

- The court denied Microsoft’s motions for partial summary judgment on the perceived incompatibilities claim.
- The court denied Microsoft’s motions for partial summary judgment on the intentional incompatibilities claim.
- The court denied Microsoft’s motions for partial summary judgment on the predisclosure/beta-testing exclusion claim.
- The court denied Microsoft’s motion for partial summary judgment on the technological tying claim based on Windows 95’s integration.
- The court declined to strike Microsoft’s briefs to the broad extent Caldera sought.

## Legal Principles

- On summary judgment, courts must view the evidence in the light most favorable to the nonmovant and deny relief where a reasonable jury could find for that party on disputed material facts.
- In antitrust cases alleging exclusionary schemes, related acts may be evaluated in context rather than treated as isolated events, particularly where intent and competitive effects depend on credibility and cumulative impact.
- Product design choices and technical warnings are not automatically lawful; where evidence supports competing inferences—legitimate technical purpose versus exclusionary strategy—resolution is for the jury.
- A firm’s discretion over predisclosure of pre-release information may still be probative of exclusionary conduct when combined with evidence of monopoly power, exclusionary intent, and anticompetitive effect.
- Technological integration is not categorically exempt from tying or monopolization scrutiny; a defendant is not entitled to judgment as a matter of law merely by characterizing integration as a plausible improvement.
- Where evidence could support findings that (1) components are separate products with distinct demand and (2) integration foreclosed rivals without sufficient efficiency justification, tying and exclusionary-conduct claims may proceed to trial.

## Conclusion

The court held that material factual disputes required a jury to decide whether Microsoft’s alleged incompatibility tactics, predisclosure practices, and Windows 95 integration were legitimate competitive behavior or exclusionary conduct that maintained monopoly power and unlawfully foreclosed DR DOS, and it therefore denied Microsoft’s partial summary judgment motions on those theories.


Caldera, Inc. v. Microsoft Corp., 72 F. Supp. 2d 1295 (D. Utah 1999)