Meeting minutes of 17 February 1960 regarding the Bougeard suspension patent

Minutes of a meeting at Citroën bringing together Paul Magès to prepare the response to the Washington Patent Office and to take stock of the Bougeard patent filings in Spain, Belgium, England, Germany and Italy.

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Understanding this document

In this document

These minutes relate to a meeting held on 17 February 1960, bringing together Messrs. Bougeard and Durand (industrial property consulting engineers), Henry-Biabaud, Paul Magès and Étiévant p. 5.

Response to the Washington Patent Office

The main objective is to prepare the response to be given to the Patent Office in Washington, following its second official letter challenging the novelty of the Bougeard patent p. 5.

Three prior patents are cited and dismissed one by one:

De Saint Senoch (DP 256.094 / BF 415.564): a triple-piston clutch control, deemed not comparable p. 5;
Mercier (BP 516.275 / DP 164.333): "does not function in a comparable way at all" p. 5;
Messier (USP 1.980.423): an aircraft landing gear, limited to a simple recharging of the shock absorber cylinder p. 5.

The document recalls the distinctive principle of the Bougeard device: communication between two chambers with unequal pressures, opening in the event of excessive pressure, closing near equilibrium, with external exhaust if the back pressure is excessive or the flow too slow p. 5. It is Mr. Durand who must draft the response, to be communicated before sending p. 5.

Status of filings by country

Country	Point raised	Page
England	Patent granted under No. 828.572	p. 5
France	July addendum to the patent	p. 5
Germany	Decision of the appeals senate confirming novelty against the Nallinger patent	p. 5
Spain	Ordinary patent possible, without priority or obligation to exploit	p. 6
Belgium	Import patent regime, situation comparable to Spain	p. 6
Italy	Bougeard presented his patent to Fiat, who responded negatively; the letter is kept as proof of implementation effort	p. 6

For Spain and Belgium, the meeting mentions the risk that a competitor might file a patent in the meantime if one waits until ready to manufacture, a risk deemed "very limited" p. 6. It is agreed to examine the decision with Mr. Falque, then to write to Bougeard to clarify Citroën's position p. 6.

Context

The name Bougeard is associated, in this collection, with work on air suspension conducted in parallel with the hydropneumatic suspension developed by Magès for the DS. At the end of the 1950s, Citroën was exploring several technical avenues before generalizing hydropneumatics; international patent protection (US Patent Office, national offices) was a strategic issue to secure these innovations against competition, particularly in the automotive and aeronautical sectors (hence the comparison with an aircraft landing gear patent like Messier).

Archivist's perspective

These minutes illustrate the legal and administrative work that accompanied, at Citroën, the filing and defense of suspension patents — an aspect less visible than the technical research itself but just as decisive for the valuation of inventions.

The presence of Paul Magès at this meeting p. 5 suggests that he was closely following, beyond his own hydropneumatic system, the competing or complementary developments proposed by Bougeard on air suspension.

This document is likely part of a larger file on this matter, as evidenced in particular by the note from Magès of 19 June 1961 summarizing the Bongrand affair and the B.E.A. meeting sheet of 17 January 1961 comparing air and hydropneumatic suspension.