About some strange RF PDK symbols

[gaom9]

Hi,
I have a question about the PDK symbols. I used the PDK symbols to make the schematic of an RF design. But I find some symbols are strange as shown in the following figure. In these symbols the CAP and inductor have three pins.
What is the extra pin for? And what should it be connected to, please?

These cap and inductor are for RF design.

Thank you!
Best regards!

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[ricklin]

Parasitic cap to the shield, usually connect this shield node to ground. For detail value calculation, you can check it in the spice model.

 

[RealAEL]

This is the substrate pin or sometimes called bulk pin. It represents a connection pin in the substrate to which the device attached. As stated it is often simply grounded directly or grounded through a substrate resistance component but it can also be used to configure more elaborate device-to-device conduction paths (leakage) through the substrate material.