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17.19 Substantial Similarity—Extrinsic Test; Intrinsic Test

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As the Ninth Circuit confirmed in Antonick v. Elec. Arts, Inc., 841 F.3d 1062 (9th Cir. 2016), the court employs a two-part test for determining whether one work is substantially similar to another:

[A plaintiff] must prove both substantial similarity under the "extrinsic test" and substantial similarity under the "intrinsic test." The "extrinsic test" is an objective comparison of specific expressive elements. The "intrinsic test" is a subjective comparison that focuses on whether the ordinary, reasonable audience would find the works substantially similar in the total concept and feel of the works.

Id. at 1065-66; see also Williams v. Gaye, 885 F.3d 1150, 1163 (9th Cir. 2018) (approving instructions and explaining that extrinsic test requires "analytical dissection of a work and expert testimony"). The Committee recommends that the court and counsel specifically craft instructions on substantial similarity based on the particular work(s) at issue, the copyright in question, and the evidence developed at trial. The following cases may provide guidance in formulating substantial similarity instructions in specific subject areas:

Literary or Dramatic Works: Shaw v. Lindheim, 919 F.2d 1353, 1357 (9th Cir. 1990); Sid & Marty Krofft Television Prods. v. McDonald’s Corp., 562 F.2d 1157, 1164 (9th Cir. 1977) (holding that commercials infringed television production; applying specific criteria to assessment of substantial similarity); see also Corbello v. Valli, 974 F.3d 965, 975 (9th Cir. 2020) (applying extrinsic test for similarity to elements of challenged work that are undisputedly factual); Metcalf v. Bochco, 294 F.3d 1069, 1073-74 (9th Cir. 2002) (applying Shaw factors applied to screenplay for television show); Pasillas v. McDonald’s Corp., 927 F.2d 440, 442-43 (9th Cir. 1991) (noting that Shaw "is explicitly limited to literary works" and Krofft test is still applicable to other than dramatic or literary works). 

Musical Compositions: Swirsky v. Carey, 376 F.3d 841, 848-49 (9th Cir. 2004) (noting factors and constituent elements applicable to "analyzing musical compositions," while noting that Ninth Circuit has "never announced a uniform set of factors" because "each allegation of infringement will be unique"); Newton v. Diamond, 388 F.3d 1189, 1196 (9th Cir. 2003) (noting musical elements); Three Boys Music Corp. v. Bolton, 212 F.3d 477, 485-86 (9th Cir. 2000) (identifying "areas" of similarity of musical works); Williams, 885 F.3d at 1164 (noting that musical compositions are not "confined to a narrow range of expression").  In Skidmore v. Led Zeppelin, 952 F.3d 1051, 1074, 1069 (9th Cir. 2020) (en banc), a case involving the alleged copyright infringement of a musical composition, the Ninth Circuit, reviewing for plain error, concluded that the district court did not err in omitting a “selection and arrangement” instruction. 

Computer Programs and Similar TechnologiesApple Computer, Inc. v. Microsoft Corp., 35 F.3d 1435, 1445 (9th Cir. 1994) (involving audiovisual and literary component of computer program); Brown Bag Software v. Symantec Corp., 960 F.2d 1465, 1477 (9th Cir. 1992) ("[C]omputer programs are subject to a Shawtype analytic dissection of various standard components, e.g., screens, menus, and keystrokes"); Data E. USA, Inc. v. Epyx, Inc., 862 F.2d 204, 210 (9th Cir. 1988) (involving home-computer karate game); Frybarger v. Int’l Bus. Mach. Corp., 812 F.2d 525, 529-30 (9th Cir. 1987) (involving video game). 

Motion Picture, Television Production, or Copyrighted ScriptBenay v. Warner Bros. Entm’t, Inc., 607 F.3d 620, 624-29 (2010) (involving movie and screenplay); Funky Films, Inc. v. Time Warner Entm’t Co., L.P., 462 F.3d 1072, 1076-77 (9th Cir. 2006) (involving screenplay and television series); Rice v. Fox Broad. Co., 330 F.3d 1170, 1177-78 (9th Cir. 2003) (involving video and television specials); Metcalf v. Bochco, 294 F.3d 1069 (9th Cir. 2002) (involving screenplay and television series); Berkic v. Crichton, 761 F.2d 1289, 1293 (9th Cir. 1985) (involving novel and motion picture); Litchfield v. Spielberg, 736 F.2d 1352, 1356-57 (9th Cir. 1984) (involving musical play and movie). 

"Other Than Dramatic or Literary Works":  Malibu Textiles, Inc., v. Label Lane Int’l, Inc., 922 F.3d 946 (9th Cir. 2019) (involving original selection, coordination, and arrangement of floral-pattern-printed fabric); L.A. Printex Indus., Inc. v. Aeropostale, Inc., 676 F.3d 841, 848-52 (9th Cir. 2012) (same); Mattel, Inc. v. MGA Entm’t, Inc., 616 F.3d 904, 913-14 (9th Cir. 2010) (involving toy dolls); Cavalier v. Random House, Inc., 297 F.3d 815, 826 (9th Cir. 2002) (involving works of visual art); Sid & Marty Krofft Television Prods., 562 F.2d at 1164 (providing dicta concerning application of specific criteria to plaster recreation of nude human figure); Pasillas, 927 F.2d at 442-43 (noting Krofft test applicable to other than dramatic or literary works; using test to assess similarity of Halloween mask and mask used in television commercial).

 "Ordinary Observer" Test:  Micro Star v. Formgen, Inc., 154 F.3d 1107, 1112 (9th Cir. 1998) (applying ordinary reasonable person standard); see also L.A. Printex Indus., Inc., 676 F.3d at 852 (involving fabric designs); Johnson Controls Inc. v. Phoenix Control Sys., 886 F.2d 1173, 1176 n.4 (9th Cir. 1989) (involving computer software), implied overruling on other grounds recognized by Perfect 10, Inc. v. Google, Inc., 653 F.3d 976, 979 (9th Cir. 2011); Data E. USA, Inc., 862 F.2d at 209-10 (discussing intended audience); Aliotti v. R. Dakin & Co., 831 F.2d 898, 902 (9th Cir. 1987) (involving perception of children); Berkic, 761 F.2d at 1293 (discussing reasonable reader or moviegoer).  

Revised Sept. 2020