It's My Party, Inc. v. Live Nation, Inc., 811 F.3d 676

It’s My Party, Inc. (IMP) is a regional concert promoter/operator (Merriweather Post Pavilion in Columbia, MD); Live Nation, Inc. (LN) is a national promoter and venue operator (Nissan Pavilion/Jiffy Lube Live in Bristow, VA) that also acquired Ticketmaster.
IMP sued under §1 and §2 of the Sherman Act (and parallel Maryland law) alleging monopolization, tying, and exclusive dealing that foreclosed competition for concert promotion and amphitheater venues in the Washington–Baltimore area.
IMP framed two relevant markets: a national concert-promotion market and a narrow “major amphitheater” venue market (8,000+ capacity, May–September use), which in the region included only Merriweather and Nissan.
The district court excluded parts of IMP’s expert venue-market analysis, concluded the promotion market is local (not national), rejected the amphitheater-only market definition, and granted summary judgment for LN.
On appeal the Fourth Circuit affirmed: IMP failed to define plausible relevant markets and failed to show coercive tying or other anticompetitive conduct; evidence showed artists often freely chose LN venues for competitive reasons (better pay, package deals, venue attributes).

Issue	Plaintiff's Argument	Defendant's Argument	Held
Proper market definition for promotion	Promotion is national; LN’s national scale shows market power	Promotion is local; artists and advertising demand are region-specific	Promotion market is local (Washington–Baltimore); IMP’s national market definition rejected
Venue market definition	Concert venue market limited to "major amphitheaters" (8,000+ capacity, seasonal)	Venue market includes reasonably interchangeable venues (arenas, stadiums); amphitheaters not a distinct market	Amphitheater-only market not shown; IMP failed to prove venues were not reasonably interchangeable
Tying (venue↔promotion or venue↔venue)	LN conditions promotion or access to other LN amphitheaters on artist playing Nissan (coercion)	LN offers packages; artists freely choose due to better compensation, efficiency, or venue quality; no coercion	No tying: plaintiff failed to show coercion; substantial separate sales and market-based explanations rebut tying claim
Monopolization / exclusive dealing / state-law claims	LN’s size, exclusive rights and integrated network foreclose competition	Size and integration reflect competitive success and efficiencies, not unlawful foreclosure; no anticompetitive conduct shown	Monopolization and related claims fail; state-law claims fail in tandem; summary judgment for LN affirmed

E.I. du Pont de Nemours & Co. v. FTC, 351 U.S. 377 (1956) (market definition and interchangeability analysis)
Eastman Kodak Co. v. Image Technical Servs., 504 U.S. 451 (1992) (cross-elasticity and tying-market power considerations)
Jefferson Parish Hosp. Dist. No. 2 v. Hyde, 466 U.S. 2 (1984) (tying doctrine centers on coercion and forced purchase)
Times-Picayune Pub. Co. v. United States, 345 U.S. 594 (1953) (importance of "forced purchase" in tying claims)
Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574 (1986) (plaintiff must exclude plausible procompetitive explanations)
United States v. Microsoft Corp., 253 F.3d 34 (D.C. Cir. 2001) (bundling and efficiencies; consumer choice as touchstone)
Verizon Commc’ns Inc. v. Law Offices of Curtis V. Trinko, LLP, 540 U.S. 398 (2004) (monopoly power and procompetitive investments)
Grinnell Corp. v. United States, 384 U.S. 563 (1966) (distinguishing monopoly power from unlawful conduct)
Monsanto Co. v. Spray-Rite Serv. Corp., 465 U.S. 752 (1984) (circumstantial proof standards requiring exclusion of competitive explanations)
Serv. & Training, Inc. v. Data Gen. Corp., 963 F.2d 680 (4th Cir. 1992) (circumstantial proof in tying claims)
E.I. du Pont de Nemours & Co. v. Kolon Indus., 637 F.3d 435 (4th Cir. 2011) (geographic market defined by where customers can practicably turn for alternatives)