Louis-Simon Boizot (1743-1809) was the director of sculpture at Sèvres from 1773 to 1809. His arrival was timely; models were needed for the new hard paste, in full production from 1772. He chiefly designed biscuit groups. Bourgeois lists almost 150 groups designed by Boizet before the revolution, many representing classical history and mythology.
Biscuit figures made from 1773-1780 are inscribed BO as the above.
Cf. R. Savill, The Wallace Collection, Catalogue of Sèvres Porcelain III (London 1988), p.967 for a discussion.