Heaven 17 is the name of the group formed by Ian Craig Marsh and Martyn Ware, previously with The Human League, together with Glenn Gregory.
The name Heaven 17 is taken directly from the novel A Clockwork Orange by Anthony Burgess where a fictitious group named "The Heaven Seventeen" is mentioned by Alex when he visits a record shop. 
Heaven 17 were part of the umbrella production company named British Electric Foundation (or B.E.F.) also formed by Marsh, Ware and Gregory.
Links to The Human League
Apart from the obvious relationship of founder members Marsh and Ware being also founder members of The Human League, the two groups continued to have further connections since H17 began in 1981. Both groups, for example, appeared on the 1000th episode of Top of the Pops, broadcast on BBC One TV on 05 May 1983 when The Human League were at no. 3 with Keep Feeling Fascination while Heaven 17 were at no. 8 with Temptation.
Both groups, together with ABC, took part in the Steel City Tour in November and December 2008. 
- Burgess, A. A Clockwork Orange, 1962 - 50th Anniversary edition, 2012 p. 49
- theguardian.com - Riot in Steel City, Friday 28 November 2008.