The format was endorsed by William IV and Victoria, who had the conditions changed during 1837 so that mathematics was a subject for which a Royal Medal could be awarded, albeit only every third year.

The conditions were changed again during 1850 so that: ... the Royal Medals in each year should be awarded for the two most important contributions to the advancement of Natural Knowledge, published originally in Her Majesty's dominions within a period of not more than ten years and not less than one year of the date of the award, subject, of course, to Her Majesty's approval.

... in the award of the Royal Medals, one should be given in each of the two great divisions of Natural Knowledge.

During 1965, the system was changed to its current format, in which three medals are awarded annually by the monarch on the recommendation of the Royal Society Council.

Because of its dual nature (for both physical and biological science) the award winners are chosen by both the A- and B-side Award Committees.