The 40 Eridani A Starfleet Construction Yards were 24th century Federation shipyards located at 40 Eridani A in the Vulcan system.

The Miranda-class starship USS Brattain was built by Yoyodyne Division at these yards on stardate 22519.5. (TNG: "Night Terrors")

The Nebula-class starship USS Phoenix was built by Yoyodyne Division at these yards on stardate 40250.5. (TNG: "The Wounded")

The Nebula-class starship USS Prometheus was built by Yoyodyne Division at these yards. (DS9: "Second Sight")

After the attack on Mars in 2385, Admiral Jean-Luc Picard and Commander Raffaela Musiker proposed to Starfleet that mothballed ships from Eridani A and Beta Antares be used to maintain the evacuation of Romulans from the Romulan supernova, albeit at a severely reduced level. The proposal was rejected. (PIC: "The End is the Beginning")

A star chart

It had not been canonically established that 40 Eridani A is located in the Vulcan system until a draft of Geoffrey Mandels Book Star Trek: Star Charts was used in various ENT episodes which shows the location of
"Vulcan (40 Eridani A)".
Until their mention in PIC: "The End is the Beginning", the existence and location of these shipyards was not known from aired dialogue, but had been derived from the text of the starship dedication plaques.
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