At VanityFair.com:
"Picasso was exceedingly generous with his work, but he never gave away anything from earlier periods, always from whatever he was working on at the time and available in the studio. Also, when he gave someone a drawing or a print, he always signed and also inscribed it. Of the 271 works said to be in Le Guennec’s cache, reportedly only one of them bears the artist’s signature, and none of them is inscribed."
Also:
"The Le Guennec affair puts me in mind of the large collection of works, mostly on paper and mostly executed at the end of the artist’s life, belonging to the heir of his driver, Maurice Bresnu, which appeared on the market in the 1990s. Bresnu (nicknamed 'Nounours') and his wife endeared themselves to the Picassos. At first mistakenly thought to have been fakes and, later, to have been stolen—only a fraction had been inscribed—they were ultimately O.K.’d by the Picasso administration and put up for sale at Christie’s (November 19, 1998). It will be interesting to see how the Picasso administration, not to mention the French judiciary, reacts in this new, far graver case."