While the NBA has a “soft cap” in most circumstances, taking advantage of certain privileges only teams under the apron (exactly $4 million above the luxury tax line) enjoy forces teams to be hard capped at the apron for the remainder of that league year. If you want to read more on the hard cap, you can check out my piece on it.
Larry Coon has the full list of actions that can hard cap a franchise in his CBA FAQ but the three main ones are using the Non-Taxpayer Mid-Level Exception (larger than the Taxpayer MLE), the Bi-Annual Exception, or acquiring a player via sign-and-trade.
These franchises are subject to the hard cap for the 2014-15 season:
Atlanta Hawks – Acquired Thabo Sefolosha via sign-and-trade from the Oklahoma City Thunder.
Golden State Warriors — Agreed to a contract with Shaun Livingston worth the full Non-Taxpayer Mid-Level Exception.
Houston Rockets — Acquired Trevor Ariza via-sign-and-trade from the Washington Wizards.
Indiana Pacers — Agreed to a contract with CJ Miles worth a sufficiently high amount of the Non-Taxpayer Mid-Level Exception.
Los Angeles Clippers – Agreed to a contract with Spencer Hawes worth the full Non-Taxpayer Mid-Level Exception and used the Bi-Annual Exception on Jordan Farmar.
Memphis Grizzlies — Signed Vince Carter for a sufficiently high portion of the Non-Taypayer Mid-Level Exception and reportedly agreed to use the Bi-Annual Exception on Beno Udrih.
Phoenix Suns — Acquired Isaiah Thomas via sign-and-trade from the Sacramento Kings.
Portland Trail Blazers – Agreed to a contract with Chris Kaman worth a sufficiently high amount of the Non-Taxpayer Mid-Level Exception. Also agreed to use their Bi-Annual Exception on Steve Blake.
Sacramento Kings – Agreed to a contract with Darren Collison worth a sufficiently high amount of the Non-Taxpayer Mid-Level Exception.
Washington Wizards – Agreed to a contract with Paul Pierce worth the full Non-Taxpayer Mid-Level Exception.
[AUTHOR'S NOTE: The Miami Heat were on this list previously because of the contracts they agreed to with Josh McRoberts and Danny Granger. Due to the events that transpired after those agreements, the Heat ended up using cap space rather than exceptions to sign them so the team is not hard capped.]