The first change in Swiss law on arms exports came via a Federal Council decree of March 28th 1949. This decree doesn't appear to be available digitally, but is described by Sabine Widmer as follows:
This Decree confirmed the already existing general ban on the export
of weapons and other so-called war materials. However, the Defence
Technology Division (DTD) of the FMD, could, after consultation with
the FPD, exceptionally grant export permits. Behind the scenes, the
general ban on arms exports was softened almost immediately. The Swiss
arms industry lobbied the Federal Council to liberalise its policy,
arguing that exports were necessary to maintain the independent and
technologically advanced armament industry that was essential for
Switzerland’s national defence. Many FMD members shared this view.
In practice, a procedure was established whereby companies had to
request permits both for the fabrication of specific war materials and
for their export. Applications for export to countries where armed
conflicts were taking place or threatened to break out were not to be
granted. However, this restriction was treated rather flexibly. Thus,
exports to warring parties might be authorised if there was a written
guarantee that the arms delivered by Swiss firms would not be used in
the conflict. Nevertheless, the Federal Council introduced export
bans or restrictions for specific states and regions, notably Israel
and the Arab countries in 1955, South Africa in 1963, and Rhodesia in
1965.
In 1972, in response to a popular initiative "for the reinforced control of arms industries and for the prohibition of arms exports", a law on war materiel was passed in June. Again, this doesn't appear to have been digitised, but is partially described by Le Temps - ironically describing how Switzerland exported arms to Pinochet in Chile.
The Federal Law on War Material (of 30 June 1972) states in Article 4
that "trade in war material" is prohibited "except with the initial
authorisation of the Confederation". However, Article 11 states that
no permit shall be issued "to territories where armed conflicts have
broken out or are threatening to break out or where dangerous tensions
exist"; or "if it appears that deliveries of war material to a given
country are likely to compromise the efforts of the Confederation in
the field of international relations, in particular with regard to
respect for human dignity, humanitarian aid or development aid."
This law was updated in 1996, again, in response to a popular initiative "for the prohibition of the export of war materiel". This version is digitised on the Swiss federal website, and this law is the one referred to in the June 2022 statement from the Federal Council regarding sending war materiel to Ukraine.
