Macgregor v. Westinghouse Electric & Manufacturing Co.
329 U.S. 402 · Decided January 6, 1947 · Supreme Court of the United States
At a glance
Macgregor v. Westinghouse Electric & Manufacturing Co. was decided on January 6, 1947 by a vote of 5–4. The Court reversed the lower court's decision and remanded the case. Justice Hugo L. Black wrote the opinion of the Court. SCDB classifies its main issue as “Patents” in the Economic Activity area. SCDB codes this decision as formally altering one or more of the Court's own precedents.
Read the opinion
Case details
- Citations
- 329 U.S. 402 · 67 S. Ct. 421 · 91 L. Ed. 380 · 1947 U.S. LEXIS 3020
- Docket number
- 28
- Decided
- January 6, 1947
- Argued
- December 12, 1946
- Court era
- Vinson Court
- Decision type
- Opinion of the Court (orally argued)
- Disposition
- Reversed and remanded
- Outcome for petitioner
- The petitioning party received a favorable disposition
- Vote
- 5–4
- Majority opinion
- Hugo L. Black
- Opinion assigned by
- Fred M. Vinson
- How the case arrived
- Rehearing or restored to calendar for reargument
- Issue (SCDB)
- Patents
- Issue area
- Economic Activity
- Legal provision
- Estoppel
- Type of law
- Other
- Altered precedent
- Yes — formally altered the Court's precedent
- Decision direction (SCDB)
- Liberal what this means
How the Justices voted
| Justice | Vote | Separate writing |
|---|---|---|
| Justice Hugo L. Black | Majority | Wrote an opinion |
| Justice Stanley F. Reed | Dissent | |
| Justice Felix Frankfurter | Dissent | Wrote an opinion |
| Justice William O. Douglas | Majority | |
| Justice Frank Murphy | Majority | |
| Justice Robert H. Jackson | Dissent | |
| Justice Wiley B. Rutledge | Majority | |
| Justice Harold H. Burton | Dissent | |
| Chief Justice Fred M. Vinson | Majority |
Full case caption
Macgregor v. Westinghouse Electric & Manufacturing Co.
SCDB identifiers: case 1946-027, docket 1946-027-01.
Related decisions
Other cases on “Patents”
- Edward Katzinger Co. v. Chicago Metallic Manufacturing Co.
- Transparent-Wrap Machine Corp. v. Stokes & Smith Co.
- Halliburton Oil Well Cementing Co. v. WalkerAltered precedent
- Funk Brothers Seed Co. v. Kalo Inoculant Co.
- Mandel Brothers, Inc. v. Wallace
- Jungersen v. Ostby & Barton Co.
Cases on the same legal provision: Estoppel
- Commissioner of Internal Revenue v. Sunnen
- United States v. International Building Co.
- Callanan Road Improvement Co. v. United States
- Partmar Corporation v. Paramount Pictures Theatres Corp.
- Kennedy v. Mendoza-MartinezLaw held unconstitutional
- Federal Power Commission v. Amerada Petroleum Corp.
Same Term, same area (Economic Activity)
- Halliburton Oil Well Cementing Co. v. WalkerAltered precedent
- Champlin Refining Co. v. United States
- United States v. Howard P. Foley Co., Inc.
- Richfield Oil Corp. v. State Board of EqualizationLaw held unconstitutional
- American Power & Light Co. v. Securities & Exchange Commission
- Vanston Bondholders Protective Committee v. Green
Source: Supreme Court Database, 2026 Release 01 (data file dated September 8, 2026). Imported into CaseTrail November 5, 2026. Coverage: decisions from the 1946 through 2025 Terms. Methodology · Report an error