Anybody can copy an 'insubstantial amount'. This is not defined in law, but almost certainly precludes anything materially useful by itself. A single copy of a 'substantial amount' may be copied under fair dealing for private study or for research for a non-commercial purpose, and the generally accepted upper limits of what constitutes a substantial amount that can be copied within 'fair dealing' is as follows:
- One photocopy of one article in a serial publication or in a set of conference proceedings or in a collective work (other than a poem, short story or other literary work in a collection of such works);
- One photocopy of one complete chapter from a book;
- One photocopy of one case report from a law report;
- Up to 5% of a physical volume of any of the above (which may be greater than one article, chapter or report, or may include extracts from more than one such article, chapter or report);
- One short story or poem in a collective work, up to ten pages in length.
Any more than this is not fair dealing. Nor is it fair dealing to copy, say, one article from a book or journal on one occasion and another article from the same book or journal on another occasion. Note also that introductory and similar matter (title pages, contents lists, bibliographies, notes) are not excluded: in a single work they are part of the work and count for decisions on the amount and whether the extracts are separate or not; in a compilation or a critical edition they are separate works.
There is no overall agreement about downloading from electronic journals. Licence conditions vary, and should always be checked. In general, however, you should not try to download more than the amounts indicated above.