He and other notable members of the CNT had previously signed a Manifest dels Trenta ("Manifesto of the Thirty"), which had got them expelled.

[2] The thesis of Ángel Pestaña was to contribute to the workers' movement by endowing it with a political party which, without interfering in their work, collaborated with the industrial unions, but with full autonomy.

It differed from the PSOE-UGT pact in that it intended to avoid all subordination of union work to partisan political interests.

Pestaña's libertarian possibilist tendency corresponded with the British Independent Labour Party, a representation of workers' interests in Parliament with a revolutionary purpose; that is, the achievement of libertarian communism with an organization based on the cooperatives, trade unions and municipalities.

Only a minority in the CNT, the possibilist tendency was isolated due to its moderate syndicalist stance, and depended on several cells in Madrid, Andalusia, Zaragoza, Catalonia, and Valencia.