Treasury Secretary Steven Mnuchin will require public companies deemed critical to national security that seek a share of $17 billion in virus-related relief to offer an equity stake to the government.

For private companies, Mnuchin “may, in his discretion, accept senior debt instruments” or other financial interests, the Treasury Department said in the 10-page loan application posted on its website late Thursday.

The requirements are similar to those for passenger and cargo airlines seeking payroll assistance from the $2.2 trillion coronavirus stimulus package passed by Congress.

Borrowers must have a priority level contract with the government and currently operate under a “top secret facility clearance,” according to the application on Treasury’s website late Thursday.

The agency set a May 1 deadline, although it will still consider applications that come in later based on the availability of funds.

“This pot of money was designed to consider the needs of defense contractors, key suppliers to DOD and other companies that carry classified information,” Mnuchin said Thursday in an interview, referring to the Defense Department.

One obvious contender for the funds is Boeing Co. which has so far said it might not request government support. Mnuchin said he has had multiple conversations with Boeing’s top executives but declined to say whether it intended to tap government funds.

Boeing is poised to cut its 787 Dreamliner output by about half and announce workforce reductions when it reports first-quarter earnings next week, people familiar with the plans said on Thursday.