Look-Through Earnings

Biological Parallel

Mycorrhizal fungi don't photosynthesize—they acquire carbon by colonizing tree roots. To assess a fungus's resource intake, you must look through its network to the trees feeding it. The fungus's 'earnings' are the trees' photosynthesis, delivered via underground exchange. Buffett's look-through earnings applies identical logic: holding companies don't create value directly; you must look through to subsidiaries' actual earnings to assess economic reality.