Albrecht Graf von Goertz (1914–2006) came from Brunkensen near Hanover, went to the USA in the 1930s and set up there as an independent industrial designer in 1953. He became known above all for the BMW 503 and 507 sports cars of 1955; he also designed, among other things, a camera for Agfa, clocks for Kienzle and appliances for Rowenta (Wikipedia).
At Montblanc his name stands for the writing instruments with which Montblanc redesigned its entire range in 1960; the Meisterstück 142, 144 and 146 were dropped at that point (“Collectible Stars” II; model catalogue). The new fountain pens were smaller and slimmer and were built on a modular system from shared parts, in two sizes: the numbers ending in 2 are about 128 mm long (closed) with a barrel diameter of 11.5 mm, those ending in 4 about 135 mm with 12 mm (forum post of 20 November 2005). The lines differ at the cap: the Meisterstück 12 and 14 with a cap ring shaped like a cardinal’s hat, also called the “bishop’s mitre”, the second line 22 and 24 with two cap rings and the third line 32 and 34 with one ring; ballpoints such as the Meisterstück 18 were added. The 149 remained in the range (forum post of 2 March 2005).
That these shapes came from Goertz is reported in forum posts: his design drawings for Montblanc were on show at an exhibition in Bremen for his 85th birthday (forum post of 3 May 2005) it was an official collaboration (post on Penexchange (thread “Die ‘kleinen’ Geschichten zu und hinter Füllhaltern”)). “Collectible Stars” II confirms that Goertz was working with Montblanc at that time, but does not name him as the designer of the new range (“Collectible Stars” II).
For the cardinal’s hat of the Meisterstück 12 and 14 the same book states explicitly that Goertz had no part in its creation, although publications attribute this cap to him. It was meant to set the most expensive line visibly apart from the cheaper ones despite the shared parts; according to the book the model was even shown at the Museum of Modern Art in New York (“Collectible Stars” II). In contrast, forum posts, including one, regard the “bishop’s mitre” as a design by Goertz (post on Penexchange (thread “Die ‘kleinen’ Geschichten zu und hinter Füllhaltern”)).
From 1971 the shapes were revised: a flat cap top and new numbers such as 120, 220 and 320 (“Collectible Stars” II). The second line then lived on as the “Classic” into the 1990s (forum post of 2 March 2005). According to forum posts, production of the new shapes began as early as 1959 (forum post of 3 May 2005), and Montblanc is said to have asked Goertz for a design in 1956 or 1957 (forum post (Fountain Pen Network) of 26 October 2018); the reference works give 1960. Short-lived intermediate forms are described under the transitional models 142, 144 and 146.