Owner of at least 600 ha[6] and devoted to agriculture and horticulture, he published in various periodicals, served as president of Sindicato Agrícola Vizcaíno and Junta Provincial de Agricultura; he was also active supporter of Basque culture, initiating Fiestas Eúskaras and similar festivals.

Ampuero Jáuregui engaged in industry, co-founding Ferrocarril Central de Bizkaia[7] and holding stakes in numerous enterprises from mining and metallurgy business.

[32] José Joaquín started to replace his father in executive boards of various companies in the mid-1900s;[33] at the same time he was setting up own enterprises,[34] represented Biscay diputación in firms controlled by the provincial self-government,[35] and got engaged in businesses of his in-laws, the Gandarias Durañona family.

[37] Ampuero's pivotal role was ensured by his membership in executive of Banco de Bilbao;[38] he represented the bank in supervisory boards of numerous companies where BdB was one of major shareholders.

[43] The related machinery business was represented by Basconia,[44] Fundiciones Vera,[45] Talleres de Gernica, Combustión Racional,[46] Construcciones Electro-Mecánicas[47] and Maquinaria Eléctrica;[48] apart from sitting in their management boards, Ampuero co-founded some of these companies.

[70] Under his own name he provided local correspondence,[71] wrote brief biographies of Traditionalist pundits,[72] spoke against secularization tide at the universities,[73] defended Basque fueros[74] or even published poems, like the one dedicated to the new wife of Carlist king Carlos VII, Berthe de Rohán.

[77] None of the sources consulted confirms engagement in party structures; however, in wake of Carlist conspiracy and few minor disturbances of late 1900, known as La Octubrada, he was briefly detained.

[78] Before turning 30 Ampuero was catapulted to public power when in 1901 and thanks to the role and position enjoyed by his father, he was elected from the district of Durango to the Biscay diputación provincial, the local self-government;[79] as a Carlist candidate he would be re-elected for two successive terms, commencing in 1905[80] and 1909.

In 1918 he was heavily inclined towards a broad right-wing coalition with the Alfonsists and nationalists; the faction, known as La Piña, was ridiculed by orthodox Jaimistas as “piñosos con boinas”.

Ampuero decided to join the dissenters; he entered their local executive, Junta Señorial Tradicionalista de Vizcaya,[101] and with Ignacio Gardeazábal was co-leading the Biscay Mellistas.

[103] Banking on prestige of late Ampuero Jáuregui, own position as business tycoon, Traditionalist following in the province and conciliatory approach towards other parties, he was comfortably elected; his seat was confirmed for the following legislatures of 1921,[104] 1922 and 1923.

[113] Following the Primo coup he withdrew into business, refrained from any political activity and is not known for taking part in primoderiverista institutions, though his corporate engagements at times brought him closer to the officialdom.

[115] His only initiative was co-signing a 1931 letter addressed to president Niceto Alcalá-Zamora, which protested secularization policy, asked that Catholic rights be respected and religious orders be left unmolested.

[116] Ampuero died due to intracerebral hemorrhage he suffered when returning from religious service for the souls of guardias civiles, killed during so-called Sucesos de Castilblanco.