Double signature of makers on the spoon

[Johnny17]

Hello everyone,
I have a question regarding the double mark of the producers. I have two nearly identical spoons in my collection. The attached photos show the manufacturer's smaller signature, which is under the Henri Chenaillier signature. To which silversmith does the smaller sign belong?
How can this be explained and how is it possible?
Best regards

[blakstone]

The smaller mark is that of Louis Cottat, flatware maker, 41 rue de Turbigo, registered 6 Sep 1865 and cancelled 5 Nov 1875. The firm had been in business since 18 Jun 1831 when Louis Patient Cottat registered (then at 47 quai de Horloge) a similar mark: "L. COTTAT" with the same device (calipers). Around the time this smaller mark with the initials was registered in 1865, he was joined by his son Henri Charles Louis Cottat, who continued the firm after his father's death until 1876, when the firm was closed and its models and stock bought by Henri Chenaillier (thus explaining his overstriking mark).

Louis Patient Cottat
Born: ca. 1807, son of Jean Cottat & Marie Antoinette Leroy
Married: 22 Apr 1834, to Narcisse Marguerite Barberon
Died: 12 Mar 1870

Henri Charles Louis Cottat
Born: 14 Jun 1837, son of Louis Patient Cottat & Narcisse Margeurite Barberon
Married: 6 Dec 1866, to Eulalie Boutin
Died: 30 May 1915

[Johnny17]

Amazing news, I'm excited about the history of this item. Thank you very much Blackstone for your time to answer my question and explaining this to me. I greatly appreciate you.
I am curious if there have been more cases like this.
Best regards