Interesting read, page-7

Marathon Oil Corporation has been testing out 40-acre spacing on its Eagle Ford acreage, and so far eight of its wells targeting the oil and gas condensate portions of the play have posted strong production results.
160 to 80 to 40
Five of those wells targeted the oil heavy part of the play, with an average 24-hour IP rate of 1,840 BOE/d. The other three wells tapped into the gas condensate portion of the Eagle Ford, with an average initial production rate of 2,100 BOE/d.
While the IP rates were strong, pointing towards the efficacy of the program, there is room for improvement. The recovery rates of these wells ranged from 80% - 90% of the recovery rate on 80-acre spacing, with two wells coming very close to matching the recovery rate on 80-acre spacing. As Marathon continues testing out 40-acre spacing, it will be able to boost its recovery rate, just as it did in the past when it moved from 160-acre to 80-acre spacing.
Even if the recovery rate has room to grow, 24-hour IP rates around 2,000 BOE/d point towards Marathon's pilot project being very successful, which should allow it to book additional drilling locations in the future. Previous downspacing efforts grew Marathon's Eagle Ford drilling inventory from 900 to 2,300, as its 2P reserve base jumped from 469 million BOE to 1 billion BOE. Going forward, Marathon could unlock more than 1.7 billion BOE from its Eagle Ford position