No, it only allows for two cards. We use the card guides inside to help secure the table in. You coudl probably move the legs in to allow for a 3rd card. We just posted the .step file so you can easily edit the table to use your own numbers.
Note: The holes are not perfect from table to digital sidecar, but this was done so that the leg would fit against the empty slots, making a tight fit. Use zip ties to connect the DS to table for best results.
Here's the link to .step and .stl files.
http://www.thingiverse.com/thing:237694/