can anyone explain the ownershit percentages

The well was operated by the joint-venture company GEP which holds an 80% working interest in the Block. Aspect Holdings, LLC through its Aspect Energy International LLC subsidiary has a two thirds interest and ShaMaran, through its wholly owned subsidiary, ShaMaran Ventures BV, holds a 33.5% interest in GEP. Marathon Petroleum KDV B.V., a wholly owned subsidiary of Marathon Oil Corporation (NYSE:MRO), holds a 20% interest in the block.