It’s a good year to be a law firm near the end of its lease in Washington. Commercial vacancy rates have hit double digits for the first time in more than a decade, driving landlords to make valuable concessions.

Some of Washington’s largest law offices could profit. With leases expiring in the next few years, Skadden, Arps, Slate, Meagher & Flom; Arnold & Porter; Covington & Burling; and McDermott Will & Emery are among those considering a move.