International law firm Covington & Burling is representing retail colossus WalMart in Washington for lobbying issues related to government insurance plan Tricare, which provides benefits to armed services members, retirees and their families.

The Tricare program, which is managed by the Defense Health Agency under the Assistant Secretary of Defense, could see a reorganization of its current structure, the result of a $524 billion Defense Department budget request sent to Congress in February as part of the White House’s 2017 budget proposal. That proposal could also result in Tricare co-pay hikes and may require participants to pay annual enrollment fees.

The C&B team working the WalMart account includes William Wichterman, former special assistant to President Bush and senior policy advisor to Senate Majority Leader Bill Frist (R-TN); Roger Zakheim, former general counsel and deputy staff director for the House Armed Services Committee and deputy assistant secretary of defense for the Department of Defense; and Muftiah McCartinm, former staff director on the House Rules Committee. Covington & Burling is the largest law firm in Washington, D.C.

Bentonville, AR-based WalMart shelled out $6.7 million in lobbying-related fees in 2015 and $7 million the year prior.