I guess NYDIG is focusing fully on mining and AI compute:

The transaction expands BitGo’s institutional service offering and allows NYDIG to focus its resources on its vertically integrated power generation, bitcoin mining, and high-performance computing (“HPC”) data center development business, with a development pipeline exceeding 3 GW and more than 1 GW deliverable in 2027 and 2028.

BitGo is one of the companies that a number of "collaborative custody" companies use for holding keys. They are also a qualified custodian.

The transaction is expected to further strengthen BitGo’s position as a comprehensive digital asset infrastructure company, enabling institutions to access a broader range of trading and capital markets services through an integrated platform. As part of the transaction, approximately 30 NYDIG employees joined BitGo, along with NYDIG's institutional client trading relationships.

“Institutions increasingly want to work with a trusted partner that can support the full lifecycle of digital assets – from custody and trading to financing and settlement,” said Mike Belshe, CEO and Co-founder of BitGo. “We believe this transaction will meaningfully scale our trading and infrastructure capabilities and adds an exceptional team with experience serving institutional clients. It is also expected to enable us to serve a broader base of sophisticated clients that we believe will benefit from BitGo’s comprehensive infrastructure offerings. We are excited to deliver a more integrated experience for clients while creating efficiencies across technology, operations, and compliance.”