The AP1/40, indicates the number of this limited edition bronze. AP stands for Artist Proof. The number 1 after it, indicates that it is number one of 4 AP's. /40 means or indicates the number of numbered copies in the edition. This one is considered an un-numbered copy.
I went to the foundry to check the bronze for any blemishes or un-attached parts. Only found a couple of blemishes and got those fixed quickly. Only one item that needed to be fabricated and added on. You can see all this in the video, linked above.