Do you mean originally? ULA is a 50/50 joint venture that Boeing and Lockheed Martin were forced into after almost corporate-espionaging themselves into oblivion. It owns, operates, and manufactures the factories and rockets that each company used to provide independently — Delta from Boeing and Atlas from Lockheed.
>It was formerly operated by Lockheed Martin and is now operated by United Launch Alliance (ULA), a joint venture with Boeing.
https://twitter.com/torybruno/status/580076118339756034
https://twitter.com/torybruno/status/887340287550345216