A nonprofit set up to assist with President Donald Trump’s transition into office gave $150,000 to a mysterious dark money group established to support Trump officials, a new tax filing for the transition group shows. The new pro-Trump entity recently sponsored a reception for Trump appointees at the Trump hotel. It does not reveal its donors, however, leaving the public in the dark about who is behind its spending.

The contribution builds on a trend of key parts of Trump’s political operation giving money to the new group, The 45 Alliance, even before it had any public profile. The flow of money suggests The 45 Alliance may be a burgeoning pro-Trump player that’s still revealing the exact role it will play.

The transition group, Trump for America, is its third known donor. Filings with the IRS and Federal Election Commission show The 45 Alliance received $150,000 from America First Policies, another pro-Trump dark money group, as well as $75,000 from the RNC in 2018.

The 45 Alliance was formed in August of 2018, according to a corporate filing in Virginia. The three officers named on the form—Jamie Burke, Richard Dearborn, and Josh Pitcock—each have ties to the Trump administration. Dearborn and Pitcock both worked in the Trump White House, and all three worked on the transition team, perhaps providing a clue as to why the transition group is funding the new nonprofit. All three now work in private sector jobs with close ties to special interests.

The group made a splashy public debut in November by hosting a “cocktail reception” at the Trump hotel “to connect with fellow President Trump appointees and celebrate your continued dedication and service,” while also putting cash in President Trump’s pocket through the hotel. The reception also raises questions regarding compliance with gift rules by executive branch employees who attended the event and accepted food and beverage at the pricey private venue. Housing and Urban Development Secretary Ben Carson is reported to have attended the event.

It will be months before The 45 Alliance is required to report information about its fundraising and spending to the IRS, and even then, important information like who funds the group will not have to be revealed. Information on the group that has so far trickled out, however, suggests that it’s well-connected in the orbit of pro-Trump political and nonprofit groups, and we may be hearing more about it in months to come.