A Retrospective on U.S. v. Microsoft: Why Does It Resonate Today?

• DOI: 10.1177/0003603X20950227
• Published date: 01 December 2020
• Date: 01 December 2020
• Author: Daniel L. Rubinfeld

Article

A Retrospective on U.S. v.

Microsoft: Why Does

It Resonate Today?

Daniel L. Rubinfeld*

Abstract

The U.S. v. Microsoft case was filed in 1998, the District Court filed its opinion in 2000, and the D.C.

Circuit’s opinion came down in 2001. This article explains why the case continues to stand as an

important Sherman Act, Section 2 monopolization case. Moreover, if restated and reviewed as a two-

sided market case in light of Ohio v. Am. Express Co., the outline would be unchanged.

Keywords

Microsoft Windows, network effects, applications barrier to entry, two-sided market

The U.S. v. Microsoft case was filed in 1998, the District Court filed its opinion in 2000,

1

and the D.C.

Circuit’s opinion came down in 2001.

2

Why then is there continued interest in a twenty-year-old case

given today’s digital economy? Would the case have proceeded any differently today with our cur-

rently available industrial economics tools and in the face of the importance of two-sided markets as

spelled out in the Supreme Court’s 2018 American Express opinion? In the short paper that follows,

I explain why the case continues to stand as an important Section 2 monopolization case and why, if

restated and reviewed as a two- sided market case, it is highly li kely that the outcome would be

unchanged.

I. An Overview of the Case

In the years prior to the 1998 filing of the government’s case, it had become apparent to Microsoft that

the Netscape Navigator could serve as the foundation for a software “platform” with the potential to

compete with Microsoft’s Windows 95 (and later Windows 98) operating system (“OS”). At that time,

Microsoft’s Internet Explorer (“IE”) browser had on the order of a 30%market share, substantially less

* University of California–Berkeley, CA, USA

Corresponding Author:

Daniel L. Rubinfeld, University of California–Berkeley, 453 Law Building, Berkeley, CA 94720, USA.

Email: drubinfeld@law.berkeley.edu

1. United States v. Microsoft Corp., 87 F. Supp. 2d 30 (D.D.C. 2000).

2. United States v. Microsoft Corp., 346 U.S. App. D.C. 330, 253 F.3d 34 (2001).

The Antitrust Bulletin

2020, Vol. 65(4) 579–586

ªThe Author(s) 2020

Article reuse guidelines:

sagepub.com/journals-permissions

DOI: 10.1177/0003603X20950227

journals.sagepub.com/home/abx