Apache's share price slid 7% as it hinted at another year of cash outspend in 2018. A downgrade to year end production guidance may also have been a factor. This took shine off further derisking of its flagship Alpine High play as Apache unveiled an increase in the number of well locations to 5 000. We calculate this could translate into a valuation of US$12 billion if all the well locations are drilled up and IP and EUR rates achieved to date are replicated across the play. But we would risk this upside heavily at this early stage in the project.