Copyright, Designs and Patents Act 1988, section 21

Infringement by making adaptation or act done in relation to adaptation

Part I Copyright

(1)The making of an adaptation of the work is an act restricted by the copyright in a literary, dramatic or musical work.

For this purpose an adaptation is made when it is recorded, in writing or otherwise.

(2)The doing of any of the acts specified in sections 17 to 20, or subsection (1) above, in relation to an adaptation of the work is also an act restricted by the copyright in a literary, dramatic or musical work.

For this purpose it is immaterial whether the adaptation has been recorded, in writing or otherwise, at the time the act is done.

(3) In this Part “adaptation”—

(a)in relation to a dfnliterary [F74work, [F75 other than a computer program or a database, or in relation to aF75,F74]] dramatic work, means—

(i)a translation of the work;

(ii)a version of a dramatic work in which it is converted into a non-dramatic work or, as the case may be, of a non-dramatic work in which it is converted into a dramatic work;

(iii)a version of the work in which the story or action is conveyed wholly or mainly by means of pictures in a form suitable for reproduction in a book, or in a newspaper, magazine or similar periodical;

F76 (ab)in relation to a computer program, means an arrangement or altered version of the program or a translation of it;

F77 (ac)in relation to a database, means an arrangement or altered version of the database or a translation of it;

(b)in relation to a musical work, means an arrangement or transcription of the work.

(4) F78 In relation to a computer program a “translation” includes a version of the program in which it is converted into or out of a computer language or code or into a different computer language or code . . .

(5)No inference shall be drawn from this section as to what does or does not amount to copying a work.

Definitions used in section 21 8

made

(2)Copyright does not subsist in a literary, dramatic or musical work unless and until it is recorded, in writing or otherwise; and references in this Part to the time at which such a work is made are to the time at which it is so recorded.

Defined in s.3(2) · see it in the full Act
musical work

“musical work” means a work consisting of music, exclusive of any words or action intended to be sung, spoken or performed with the music.

Defined in s.3(1) · see it in the full Act
written

“writing” includes any form of notation or code, whether by hand or otherwise and regardless of the method by which, or medium in or on which, it is recorded, and “written” shall be construed accordingly

Defined in s.178 · see it in the full Act
writing

“writing” includes any form of notation or code, whether by hand or otherwise and regardless of the method by which, or medium in or on which, it is recorded, and “written” shall be construed accordingly

Defined in s.178 · see it in the full Act
database

(1) In this Part “database” means a collection of independent works, data or other materials which—

(a)are arranged in a systematic or methodical way, and

(b)are individually accessible by electronic or other means.

Defined in s.3A(1) · see it in the full Act
dramatic work

“dramatic work” includes a work of dance or mime; and

Defined in s.3(1) · see it in the full Act
copying

(1)The copying of the work is an act restricted by the copyright in every description of copyright work; and references in this Part to copying and copies shall be construed as follows.

Defined in s.17(1) · see it in the full Act
copy

(1)The copying of the work is an act restricted by the copyright in every description of copyright work; and references in this Part to copying and copies shall be construed as follows.

Defined in s.17(1) · see it in the full Act

Cases considering section 21 10

Trayport Limited v E-Star Trading GmbH & Ors

[2026] EWHC 164 (Ch) · 6 February 2026

Applies the pleaded case as including adaptation, but concludes that the statutory claim did not meet the merits threshold because the alleged territorial acts were not sufficiently pleaded or evidenced. (see paras [160]-[167])

PQ Systems Europe Ltd & Anor. v Jeff Aughton & Anor.

[2023] EWHC 581 (Pat) · 22 March 2023

Applies the provision to altered versions and translations of computer programs. Copying by manual or automatic translation would infringe, although the precise method was not determined.

Dr Faramarz Shayan Arani & Ors v Cordic Group Ltd

[2023] EWHC 95 (Comm) · 27 January 2023

The court relied on section 21 as part of the statutory basis for finding that PAF data had been adapted for use within CDS. (see para [58])

What each judgment says about section 21 is in the case-law panel in the full Act.

Amendments and notes

5 notes from legislation.gov.uk

Amendments

  1. F74Words in s. 21(3)(a) inserted (1.1.1993) by S.I. 1992/3233, reg. 5(1)
  2. F75Words in s. 21(3)(a) substituted (1.1.1998) by S.I. 1997/3032, reg. 7(a) (with Pt. IV)
  3. F76S. 21(3)(ab) inserted (1.1.1993) by S.I. 1992/3233, reg. 5(2)
  4. F77S. 21(3)(ac) inserted (1.1.1998) by S.I. 1997/3032, reg. 7(b) (with Pt. IV)
  5. F78Words in s. 21(4) omitted (1.1.1993) by virtue of S.I. 1992/3233, reg. 5(3)