Europe’s only exchange-traded bitcoin note, issued by XBT Provider AB, which recently surpassed $100MM in assets under management today is announcing custodial partnerships with Xapo, a Switzerland based bitcoin storage company.

As a result of the partnership, bitcoin held in cold storage on behalf of investors in XBT Provider’s ETN will now be secured by Xapo.

“The team of professionals at XBT Provider has deep expertise in digital currency and extensive experience in financial services. We are excited to partner with them as they make bitcoin broadly available to investors outside of the U.S.,” said Wences Casares, CEO of Xapo.

“In the last 60 days, XBT Provider’s exchange-traded bitcoin note has experienced unprecedented volume in trading and demand from both retail and institutional investors searching for exposure to bitcoin. This trend has quickly doubled assets under management to over the $100 million threshold,” says Jean-Marie Mognetti, Head of Trading and Operations at XBT Provider.

XBT Provider has experienced a doubling of total assets under management in the last 60 days and nearly triple in the last 6 months, and with this partnership is reiterating their commitment to security and transparency.

“The addition of Xapo to our infrastructure is a critical step in ensuring that our products remain the most professional bitcoin investment products available to investors, globally,” says Ryan Radloff, Head of Investor Relations at XBT Provider.

This news comes on the heels of last month’s announcement that the UK’s largest broker listed Europe’s only bitcoin ETN on its digital platform; and is part of a recent string of positive developments in bitcoin, internationally.