Amanda, I have been researching Jane Lend and while I found quite a few ads, I found absolutely nothing about any history of the business, or whether there was even a real Jane Lend behind the business. The greater problem for me with that is that I don't speak/read French, so I was not able to sift through things such as Parisian city directories, or trademark information, etc. Perhaps Matthew can try looking through city directories for Paris in the late 1960s, or look for trademark information about the business, etc.
The earliest reference I found to Jane Lend was in 1957:
A 1961 article about a Parisian ready-to-wear group fashion show included "firms which more closely follow fashion trends" such as Jane Lend for dresses.
A 1962 article about a "champagne fashion showing" in Washington DC "featured the designs of...Guy Laroche, Gres...Jean Desses, Jacques Heim, Jane Lend..." and others. The fashions were "French imports collected by Mrs. Adrienne Lettre, V.P. in charge of merchandising (
for Saks), on her buying trip to France."
...and I don't know if this 1964 reference to "young London designer" Jane Lend is an editorial error, or whether she lived there for a while:
Here is a photo of an ensemble by "ready-to-wear designer Jane Lend of Paris":
A Latest From Paris fashion article referred to "designer Jane Lend, famous for her discotheque dresses."
After that, IIRC, I didn't find any references to Lend in 1970+
As per my usual reminder, these images are copyrighted and the small excerpts posted here for educational purposes only. Do not reproduce them anywhere else.