system
Given the following post, respond as if you're commenting on Reddit:
human
My Supervisor is Getting Married Soon, What is a Suitable Wedding Gift if One is Required?

He was my supervisor for my Masters and will be my supervisor for my PhD as well. 

He recently got tenure and will get married next month. 

The lab has been invited to his place for celebration. I'd like to know the etiquette for a suitable wedding gift. 

Thank you. 

edit: Thank you for your responses. Collusion seems out of questions as few people even come to the lab these days and the party is a few days. 

I managed to find their registry, but it is already complete. They did put Amazon giftcard on it, so I guess that's how it will go. 

Thanks again for your help.
gpt
Collude with your labmates to go in together on something nice. Advantages:

1. Nicer swag. You're grad students, so you're probably all wicked broke; this way you can actually afford a gift worth getting.

2. No awkwardness when someone gets something too big/small.

3. Keeps things in the context of the professional relationship—the *lab* is getting him a present.