By Shane Wax
Almost everyone is familiar with Sherlock Holmes, the world’s most famous fictional detective and master of deductive logic. Less well-known is the detective’s much younger, but equally brilliant sister, Enola Holmes. In the original Sherlock Holmes stories, Sherlock’s only sibling is a brother, Mycroft, but Enola was added in a spin-off series of young adult fiction novels authored by Nancy Springer, The Enola Holmes Mysteries. This past April, Netflix announced plans to adapt The Enola Holmes Mysteries, a into a full-length film starring Millie Bobby Brown, who gained fame starring in Netflix’s Stranger Things, as the titular character, Henry Cavill as Sherlock and Helena Bonham Carter as their mother, and has confirmed a September 23 premiere date, despite the upcoming film and novel series being the subject of an intellectual property infringement lawsuit.
The Estate of Sir Arthur Conan Doyle, the original author and creator of the Sherlock Holmes characters and stories, filed a lawsuit against Springer and Netflix in federal court in New Mexico on June 23, 2020, alleging both copyright and trademark infringement. The new case presents a curious issue because the original Sherlock Holmes character is in the public domain, as explained in a 2014 opinion by the Seventh Circuit Court of Appeals that foreshadowed the current dispute:
Arthur Conan Doyle published his first Sherlock Holmes story in 1887 and his last in 1927. There were 56 stories in all, plus 4 novels. The final 10 stories were published between 1923 and 1927. As a result of statutory extensions of copyright protection culminating in the 1998 Copyright Term Extension Act, the American copyrights on those final stories (copyrights owned by Doyle’s estate, the appellant) will not expire until 95 years after the date of original publication—between 2018 to 2022, depending on the original publication date of each story. The copyrights on the other 46 stories and the 4 novels, all being works published before 1923, have expired. . . . 
The issue in the 2014 case was “whether copyright protection of a fictional character can be extended beyond the expiration of the copyright on it because the author altered the character in a subsequent work.” In other words, since the original works depicting Sherlock Holmes fell into the public domain upon the expiration of their copyright terms, does the creation of subsequent derivative works involving the same character bring the character – as depicted in those public domain works – back into the realm of copyright protection. The Seventh Circuit said no.
However, the Seventh Circuit Court of Appeals was cautious to add that “copyrights in derivative works secure protection only for the incremental additions of originality contributed by the authors of the derivative works . . . so only original elements added in the later stories remain protected” under the Copyright Act.
Which leads us to the new case against Singer and Netflix. In the new lawsuit, Doyle’s Estate claims that the later Sherlock Holmes stories, written in the aftermath of World War I in which Doyle lost a brother and son, the Sherlock Holmes character began to deviate from his old stoic, rational and analytical self and became a warmer, more emotional, more respectful, and more altruistic character. These changes, the Estate adds, led to a profound change in the relationship between Holmes and his trusty sidekick, Dr. John Watson, who became more of a friend and less of a servant to Holmes in the later books.
Doyle’s estate is counting on these post-war “incremental additions” to the character developments of Holmes and Watson to be deemed significant enough to merit protection in those modified characters as derivative works, and will undoubtedly seize on “dicta” from the 2014 case, in which the Court stated, “the additional details about Holmes and Watson in the ten late stories do indeed make for a more ‘rounded,’ in the sense of a fuller, portrayal of these characters. . . . These additional features, being (we may assume) ‘original’ in the generous sense that the word bears in copyright law, are protected by the unexpired copyrights on the late stories.” This new lawsuit will test whether those incremental additions were sufficiently original and whether the versions of Holmes and Watson appearing in Springer’s novels and the Netflix film are so similarly well-rounded to be deemed to have copies the protected expression in the derivative characters.
From a timing standpoint, as quoted above in the 2014 opinion, any expressive work authored before 1978 is given a copyright term of 95 years from the date of first publication. Therefore, any Sherlock Holmes story or character created before 1925 is now in the public domain. However, since the Copyright Act permits copyright owners to pursue a claim for any infringement occurring in the preceding three years, Doyle’s Estate can also claim infringement for any works that fell into the public domain after 1922.
The complaint against Springer and Netflix also includes a secondary cause of action for trademark infringement. Doyle’s Estate alleges that the title Enola Holmes is likely to cause confusion with a collection of Sherlock Holmes-related trademarks owned by Doyle’s Estate, such as “Sherlock Holmes,” particularly as Doyle’s Estate owns several U.S. trademark registrations in the fields of books, entertainment exhibitions, electronic gaming and clothing.
While book and movie titles and character names cannot be copyrighted under the prohibition against copyrighting words and short phrases, characters and titles of book and film series can be trademarked if “secondary meaning” can be established. For example, there is no doubt that consumers understand that the Walt Disney Company is the source of all things Mickey Mouse, and so Mickey Mouse will remain protected under the Lanham Act, even after the first Mickey Mouse publication – Steamboat Willie in 1928 – falls into the public domain in a few years. Indeed, trademark law offers an avenue of protection to owners of older creative works that have fallen into the public domain, particularly characters that are visually illustrated like Mickey Mouse or Sherlock Holmes.
In a 1979 case concerning Peter Rabbit and Other Stories – which featured a number of short stories authored by Peter Rabbit’s creator, Beatrix Potter, that had fallen into the public domain, as well as several “redrawings” of the original illustrations and cover art – the Southern District of New York denied the defendant’s motion to dismiss the trademark claims, holding that “[t]he fact that a copyrightable character or design has fallen into the public domain should not preclude protection under the trademark laws so long as it is shown to have acquired independent trademark significance, identifying in some way the source or sponsorship of the goods. . . . A character deemed an artistic creation deserving copyright protection may also serve to identify the creator, thus meriting protection under theories of trademark or unfair competition.”
However, in this case, the Doyle Estate’s trademark claims may face a timeliness issue since Springer’s first Enola Holmes novel was published in 2006 to critical acclaim (including an Edgar Award in 2007), nearly fifteen years before this suit was filed.
And speaking of timing, the final Sherlock Holmes story authored by Sir Arthur Conan Doyle was published in 1927, meaning that in two years time – 2022 – none of his works or characters will be subject to copyright laws, so we can all just get back to enjoying new films, books and spinoffs.
 See Mike Fleming, Jr., In Second Deal For Finished Film This Week, Netflix Lands Legendary’s Millie Bobby Brown-Starrer ‘Enola Holmes’, Deadline, Apr. 21, 2020, https://deadline.com/2020/04/millie-bobby-brown-enola-holmes-netflix-movie-deal-1202913756; Nancy Springer, http://www.nancyspringer.com; Penguin Random House, An Enola Holmes Mystery Series, https://www.penguinrandomhouse.com/series/DOE/an-enola-holmes-mystery.
 Tom Butler, ‘Enola Holmes’ first teaser confirms September release date, Yahoo!, Aug. 17, 2020, https://www.yahoo.com/lifestyle/enola-holmes-first-trailer-september-130720136.html
 Conan Doyle Estate Ltd. v. Springer, Case No. 1:20-CV-00610, (D.N.M.), complaint available at https://pmcdeadline2.files.wordpress.com/2020/06/sherlock-holmes-suit.pdf
 Klinger v. Conan Doyle Estate, Ltd., 755 F. 3d 496, 497 (7th Cir. 2014).
 Id., at 500.
 Id., at 501.
 See supra n.3, complaint ¶¶ 20-25.
 Dicta are statements in a judicial opinion which are not central to the case nor necessary to decide the question at hand, and therefore are not binding on other courts, but which remain persuasive.
 Klinger, 755 F.3d at 502.
 See 17 U.S.C. § 507(b).
 See supra n.3, complaint ¶¶ 41-48.
 Frederick Warne & Co., Inc. v. Book Sales Inc., 481 F. Supp. 1191, 1196-97 (S.D.N.Y. 1979) (citing Walt Disney Prods. v. Air Pirates, 581 F.2d 751 (9th Cir. 1978), cert. denied, 439 U.S. 1132 (1979); Edgar Rice Burroughs, Inc. v. Manns Theaters, 195 U.S.P.Q. 159 (C.D.Cal.1976); Wyatt Earp Enterprises v. Sackman, Inc., 157 F. Supp. 621 (S.D.N.Y.1958); Patten v. Superior Talking Pictures, 8 F. Supp. 196 (S.D.N.Y.1934)); See also Universal City Studios v. Nintendo Co., 578 F. Supp. 911, 913 (S.D.N.Y. 1983).