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ABSTRACTION-FILTRATION-COMPARISON TEST

abstraction-filtration-comparison  test.Copyright.  A  judicially  created  test  for  determining

whether substantial similarity exists between two works in an action for infringement. • In the first

step, the court dissects the copy-righted work’s structure and isolates each level of abstraction or

generality (abstraction test). In the second step, the court examines each level of abstraction and

separates   out   the   unprotectable   elements   such   as   ideas,   processes,   facts,   public-domain

information, and merger material (filtration test). In the third step, the court compares the resulting

core of protectable expression with the accused work to determine whether substantial elements of

the copyrighted work have been misappropriated (comparison test). This test was first applied by A

the Second Circuit in Computer Associates Int’l, Inc.  v.  Altai, Inc., 982 F.2d 693 (2d Cir. 1992).

Although    that    case    involved    computer    software    and    the    test    is    usu.    applied    in

software-infringement cases, the test has also been applied to nonsoftware works. — Also termed

abstraction-filtration  test.  See  SIMILARITY.  Cf.  ABSTRACTIONS  TEST.  [Cases:  Copyrights

and Intellectual Property    53(1).] [Blacks Law 8th]